Gonzales v. Raich

(Slip Opinion) OCTOBER TERM, 2004 1

Syllabus

NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
being done in connection with this case, at the time the opinion is issued.
The syllabus constitutes no part of the opinion of the Court but has been
prepared by the Reporter of Decisions for the convenience of the reader.
See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.

SUPREME COURT OF THE UNITED STATES

Syllabus

GONZALES, ATTORNEY GENERAL, ET AL. v. RAICH ET
AL.

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
THE NINTH CIRCUIT

No. 03–1454. Argued November 29, 2004—Decided June 6, 2005
California’s Compassionate Use Act authorizes limited marijuana use
for medicinal purposes. Respondents Raich and Monson are Califor-
nia residents who both use doctor-recommended marijuana for seri-
ous medical conditions. After federal Drug Enforcement Administra-
tion (DEA) agents seized and destroyed all six of Monson’s cannabis
plants, respondents brought this action seeking injunctive and de-
claratory relief prohibiting the enforcement of the federal Controlled
Substances Act (CSA) to the extent it prevents them from possessing,
obtaining, or manufacturing cannabis for their personal medical use.
Respondents claim that enforcing the CSA against them would vio-
late the Commerce Clause and other constitutional provisions. The
District Court denied respondents’ motion for a preliminary injunc-
tion, but the Ninth Circuit reversed, finding that they had demon-
strated a strong likelihood of success on the claim that the CSA is an
unconstitutional exercise of Congress’ Commerce Clause authority as
applied to the intrastate, noncommercial cultivation and possession of
cannabis for personal medical purposes as recommended by a patient’s
physician pursuant to valid California state law. The court relied
heavily on United States v. Lopez, 514 U. S. 549, and United States v.
Morrison, 529 U. S. 598, to hold that this separate class of purely lo-
cal activities was beyond the reach of federal power.
Held: Congress’ Commerce Clause authority includes the power to pro-
hibit the local cultivation and use of marijuana in compliance with
California law. Pp. 6–31.
(a) For the purposes of consolidating various drug laws into a com-
prehensive statute, providing meaningful regulation over legitimate
sources of drugs to prevent diversion into illegal channels, and
2 GONZALES v. RAICH

Syllabus

strengthening law enforcement tools against international and inter-
state drug trafficking, Congress enacted the Comprehensive Drug
Abuse Prevention and Control Act of 1970, Title II of which is the
CSA. To effectuate the statutory goals, Congress devised a closed
regulatory system making it unlawful to manufacture, distribute,
dispense, or possess any controlled substance except as authorized by
the CSA. 21 U. S. C. §§841(a)(1), 844(a). All controlled substances
are classified into five schedules, §812, based on their accepted medi-
cal uses, their potential for abuse, and their psychological and physi-
cal effects on the body, §§811, 812. Marijuana is classified as a
Schedule I substance, §812(c), based on its high potential for abuse,
no accepted medical use, and no accepted safety for use in medically
supervised treatment, §812(b)(1). This classification renders the
manufacture, distribution, or possession of marijuana a criminal of-
fense. §§841(a)(1), 844(a). Pp. 6–11.
(b) Congress’ power to regulate purely local activities that are part
of an economic “class of activities” that have a substantial effect on
interstate commerce is firmly established. See, e.g., Perez v. United
States, 402 U. S. 146, 151. If Congress decides that the “ ‘total inci-
dence’ ” of a practice poses a threat to a national market, it may regu-
late the entire class. See, e.g., id., at 154–155. Of particular rele-
vance here is Wickard v. Filburn, 317 U. S. 111, 127–128, where, in
rejecting the appellee farmer’s contention that Congress’ admitted
power to regulate the production of wheat for commerce did not au-
thorize federal regulation of wheat production intended wholly for the
appellee’s own consumption, the Court established that Congress can
regulate purely intrastate activity that is not itself “commercial,” i.e.,
not produced for sale, if it concludes that failure to regulate that class
of activity would undercut the regulation of the interstate market in
that commodity. The similarities between this case and Wickard
are striking. In both cases, the regulation is squarely within Con-
gress’ commerce power because production of the commodity meant
for home consumption, be it wheat or marijuana, has a substantial ef-
fect on supply and demand in the national market for that commod-
ity. In assessing the scope of Congress’ Commerce Clause authority,
the Court need not determine whether respondents’ activities, taken
in the aggregate, substantially affect interstate commerce in fact, but
only whether a “rational basis” exists for so concluding. E.g., Lopez,
514 U. S., at 557. Given the enforcement difficulties that attend dis-
tinguishing between marijuana cultivated locally and marijuana
grown elsewhere, 21 U. S. C. §801(5), and concerns about diversion
into illicit channels, the Court has no difficulty concluding that Con-
gress had a rational basis for believing that failure to regulate the in-
trastate manufacture and possession of marijuana would leave a gap-
 Cite as: 545 U. S. ____ (2005) 3

Syllabus

ing hole in the CSA. Pp. 12–20.
(c) Respondents’ heavy reliance on Lopez and Morrison overlooks
the larger context of modern-era Commerce Clause jurisprudence
preserved by those cases, while also reading those cases far too
broadly. The statutory challenges at issue there were markedly dif-
ferent from the challenge here. Respondents ask the Court to excise
individual applications of a concededly valid comprehensive statutory
scheme. In contrast, in both Lopez and Morrison, the parties as-
serted that a particular statute or provision fell outside Congress’
commerce power in its entirety. This distinction is pivotal for the
Court has often reiterated that “[w]here the class of activities is regu-
lated and that class is within the reach of federal power, the courts
have no power ‘to excise, as trivial, individual instances’ of the class.”
Perez, 402 U. S., at 154. Moreover, the Court emphasized that the
laws at issue in Lopez and Morrison had nothing to do with “com-
merce” or any sort of economic enterprise. See Lopez, 514 U. S., at
561; Morrison, 529 U. S., at 610. In contrast, the CSA regulates
quintessentially economic activities: the production, distribution, and
consumption of commodities for which there is an established, and
lucrative, interstate market. Prohibiting the intrastate possession or
manufacture of an article of commerce is a rational means of regulat-
ing commerce in that product. The Ninth Circuit cast doubt on the
CSA’s constitutionality by isolating a distinct class of activities that it
held to be beyond the reach of federal power: the intrastate, non-
commercial cultivation, possession, and use of marijuana for personal
medical purposes on the advice of a physician and in accordance with
state law. However, Congress clearly acted rationally in determining
that this subdivided class of activities is an essential part of the lar-
ger regulatory scheme. The case comes down to the claim that a locally
cultivated product that is used domestically rather than sold on the
open market is not subject to federal regulation. Given the CSA’s find-
ings and the undisputed magnitude of the commercial market for mari-
juana, Wickard and its progeny foreclose that claim. Pp. 20–30.
352 F. 3d 1222, vacated and remanded.

STEVENS, J., delivered the opinion of the Court, in which KENNEDY,
SOUTER, GINSBURG, and BREYER, JJ., joined. SCALIA, J., filed an opinion
concurring in the judgment. O’CONNOR, J., filed a dissenting opinion, in
which REHNQUIST, C. J., and THOMAS, J., joined as to all but Part III.
THOMAS, J., filed a dissenting opinion.
 Cite as: 545 U. S. ____ (2005) 1

Opinion of the Court

NOTICE: This opinion is subject to formal revision before publication in the
preliminary print of the United States Reports. Readers are requested to
notify the Reporter of Decisions, Supreme Court of the United States, Wash-
ington, D. C. 20543, of any typographical or other formal errors, in order
that corrections may be made before the preliminary print goes to press.

SUPREME COURT OF THE UNITED STATES
_________________

No. 03–1454
_________________

ALBERTO R. GONZALES, ATTORNEY GENERAL, ET
AL., PETITIONERS
v. ANGEL MCCLARY RAICH ET AL.
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE NINTH CIRCUIT
[June 6, 2005]

JUSTICE STEVENS delivered the opinion of the Court.
California is one of at least nine States that authorize
the use of marijuana for medicinal purposes.1 The ques-
tion presented in this case is whether the power vested in
Congress by Article I, §8, of the Constitution “[t]o make all
Laws which shall be necessary and proper for carrying
into Execution” its authority to “regulate Commerce with
foreign Nations, and among the several States” includes
the power to prohibit the local cultivation and use of mari-
juana in compliance with California law.
——————
1 See Alaska Stat. §§11.71.090, 17.37.010–17.37.080 (Lexis 2004);

Colo. Const., Art. XVIII, §14, Colo. Rev. Stat. §18–18–406.3 (Lexis
2004); Haw. Rev. Stat. §§329–121 to 329–128 (2004 Cum. Supp.); Me.
Rev. Stat. Ann., Tit. 22, §2383–B(5) (West 2004); Nev. Const., Art. 4,
§38, Nev. Rev. Stat. §§453A.010–453A.810 (2003); Ore. Rev. Stat.
§§475.300–475.346 (2003); Vt. Stat. Ann., Tit. 18, §§4472–4474d (Supp.
2004); Wash. Rev. Code §§69.51.010–69.51.080 (2004); see also Ariz.
Rev. Stat. Ann. §13–3412.01 (West Supp. 2004) (voter initiative permit-
ting physicians to prescribe Schedule I substances for medical purposes
that was purportedly repealed in 1997, but the repeal was rejected by
voters in 1998). In November 2004, Montana voters approved Initiative
148, adding to the number of States authorizing the use of marijuana
for medical purposes.
2 GONZALES v. RAICH

Opinion of the Court

I
California has been a pioneer in the regulation of mari-
juana. In 1913, California was one of the first States to
prohibit the sale and possession of marijuana,2 and at the
end of the century, California became the first State to
authorize limited use of the drug for medicinal purposes.
In 1996, California voters passed Proposition 215, now
codified as the Compassionate Use Act of 1996.3 The propo-
sition was designed to ensure that “seriously ill” residents of
the State have access to marijuana for medical purposes,
and to encourage Federal and State Governments to take
steps towards ensuring the safe and affordable distribution
of the drug to patients in need.4 The Act creates an exemp-
tion from criminal prosecution for physicians,5 as well as for
——————
2 1913Cal. Stats. ch. 324, §8a; see also Gieringer, The Origins of
Cannabis Prohibition in California, Contemporary Drug Problems, 21–
23 (rev. 2005).
3 Cal. Health & Safety Code Ann. §11362.5 (West Supp. 2005). The

California Legislature recently enacted additional legislation supple-
menting the Compassionate Use Act. §§11362.7–11362.9 (West Supp.
2005).
4 “The people of the State of California hereby find and declare that

the purposes of the Compassionate Use Act of 1996 are as follows:
“(A) To ensure that seriously ill Californians have the right to obtain
and use marijuana for medical purposes where that medical use is
deemed appropriate and has been recommended by a physician who
has determined that the person’s health would benefit from the use of
marijuana in the treatment of cancer, anorexia, AIDS, chronic pain,
spasticity, glaucoma, arthritis, migraine, or any other illness for which
marijuana provides relief.
“(B) To ensure that patients and their primary caregivers who obtain
and use marijuana for medical purposes upon the recommendation of a
physician are not subject to criminal prosecution or sanction.
“(C) To encourage the federal and state governments to implement a
plan to provide for the safe and affordable distribution of marijuana to
all patients in medical need of marijuana.” §11362.5(b)(1) (West Supp.
2005).
5 “Notwithstanding any other provision of law, no physician in this

state shall be punished, or denied any right or privilege, for having
 Cite as: 545 U. S. ____ (2005) 3

Opinion of the Court

patients and primary caregivers who possess or cultivate
marijuana for medicinal purposes with the recommendation
or approval of a physician.6 A “primary caregiver” is a
person who has consistently assumed responsibility for the
housing, health, or safety of the patient.7
Respondents Angel Raich and Diane Monson are Cali-
fornia residents who suffer from a variety of serious medi-
cal conditions and have sought to avail themselves of
medical marijuana pursuant to the terms of the Compas-
sionate Use Act. They are being treated by licensed,
board-certified family practitioners, who have concluded,
after prescribing a host of conventional medicines to treat
respondents’ conditions and to alleviate their associated
symptoms, that marijuana is the only drug available that
provides effective treatment. Both women have been
using marijuana as a medication for several years pursu-
ant to their doctors’ recommendation, and both rely heav-
ily on cannabis to function on a daily basis. Indeed,
Raich’s physician believes that forgoing cannabis treat-
ments would certainly cause Raich excruciating pain and
could very well prove fatal.
Respondent Monson cultivates her own marijuana, and
ingests the drug in a variety of ways including smoking
and using a vaporizer. Respondent Raich, by contrast, is
unable to cultivate her own, and thus relies on two care-
givers, litigating as “John Does,” to provide her with lo-
cally grown marijuana at no charge. These caregivers also

——————
recommended marijuana to a patient for medical purposes.”
§11362.5(c) (West Supp. 2005).
6 “Section 11357, relating to the possession of marijuana, and Section

11358, relating to the cultivation of marijuana, shall not apply to a
patient, or to a patient’s primary caregiver, who possesses or cultivates
marijuana for the personal medical purposes of the patient upon the
written or oral recommendation or approval of a physician.” §11362.5(d)
(West Supp. 2005).
7 §11362.5(e) (West Supp. 2005).
4 GONZALES v. RAICH

Opinion of the Court

process the cannabis into hashish or keif, and Raich her-
self processes some of the marijuana into oils, balms, and
foods for consumption.
On August 15, 2002, county deputy sheriffs and agents
from the federal Drug Enforcement Administration (DEA)
came to Monson’s home. After a thorough investigation,
the county officials concluded that her use of marijuana
was entirely lawful as a matter of California law. Never-
theless, after a 3-hour standoff, the federal agents seized
and destroyed all six of her cannabis plants.
Respondents thereafter brought this action against the
Attorney General of the United States and the head of the
DEA seeking injunctive and declaratory relief prohibiting
the enforcement of the federal Controlled Substances Act
(CSA), 84 Stat. 1242, 21 U. S. C. §801 et seq., to the extent
it prevents them from possessing, obtaining, or manufac-
turing cannabis for their personal medical use. In their
complaint and supporting affidavits, Raich and Monson
described the severity of their afflictions, their repeatedly
futile attempts to obtain relief with conventional medica-
tions, and the opinions of their doctors concerning their
need to use marijuana. Respondents claimed that enforc-
ing the CSA against them would violate the Commerce
Clause, the Due Process Clause of the Fifth Amendment,
the Ninth and Tenth Amendments of the Constitution,
and the doctrine of medical necessity.
The District Court denied respondents’ motion for a
preliminary injunction. Raich v. Ashcroft, 248 F. Supp. 2d
918 (ND Cal. 2003). Although the court found that the
federal enforcement interests “wane[d]” when compared to
the harm that California residents would suffer if denied
access to medically necessary marijuana, it concluded that
respondents could not demonstrate a likelihood of success
on the merits of their legal claims. Id., at 931.
A divided panel of the Court of Appeals for the Ninth
Circuit reversed and ordered the District Court to enter a
 Cite as: 545 U. S. ____ (2005) 5

Opinion of the Court

preliminary injunction.8 Raich v. Ashcroft, 352 F. 3d 1222
(2003). The court found that respondents had “demon-
strated a strong likelihood of success on their claim that,
as applied to them, the CSA is an unconstitutional exer-
cise of Congress’ Commerce Clause authority.” Id., at
1227. The Court of Appeals distinguished prior Circuit
cases upholding the CSA in the face of Commerce Clause
challenges by focusing on what it deemed to be the “sepa-
rate and distinct class of activities” at issue in this case:
“the intrastate, noncommercial cultivation and possession of
cannabis for personal medical purposes as recommended by
a patient’s physician pursuant to valid California state law.”
Id., at 1228. The court found the latter class of activities
“different in kind from drug trafficking” because interposing
a physician’s recommendation raises different health and
safety concerns, and because “this limited use is clearly
distinct from the broader illicit drug market—as well as
any broader commercial market for medicinal mari-
juana—insofar as the medicinal marijuana at issue in this
case is not intended for, nor does it enter, the stream of
commerce.” Ibid.
The majority placed heavy reliance on our decisions in
United States v. Lopez, 514 U. S. 549 (1995), and United
States v. Morrison, 529 U. S. 598 (2000), as interpreted by
recent Circuit precedent, to hold that this separate class of
purely local activities was beyond the reach of federal
power. In contrast, the dissenting judge concluded that

——————
8 On remand, the District Court entered a preliminary injunction

enjoining petitioners “ ‘from arresting or prosecuting Plaintiffs Angel
McClary Raich and Diane Monson, seizing their medical cannabis,
forfeiting their property, or seeking civil or administrative sanctions
against them with respect to the intrastate, non-commercial cultiva-
tion, possession, use, and obtaining without charge of cannabis for
personal medical purposes on the advice of a physician and in accor-
dance with state law, and which is not used for distribution, sale, or
exchange.’ ” Brief for Petitioners 9.
6 GONZALES v. RAICH

Opinion of the Court

the CSA, as applied to respondents, was clearly valid
under Lopez and Morrison; moreover, he thought it “sim-
ply impossible to distinguish the relevant conduct sur-
rounding the cultivation and use of the marijuana crop at
issue in this case from the cultivation and use of the wheat
crop that affected interstate commerce in Wickard v.
Filburn.” 352 F. 3d, at 1235 (Beam, J., dissenting) (cita-
tion omitted).
The obvious importance of the case prompted our grant
of certiorari. 542 U. S. 936 (2004). The case is made
difficult by respondents’ strong arguments that they will
suffer irreparable harm because, despite a congressional
finding to the contrary, marijuana does have valid thera-
peutic purposes. The question before us, however, is not
whether it is wise to enforce the statute in these circum-
stances; rather, it is whether Congress’ power to regulate
interstate markets for medicinal substances encompasses
the portions of those markets that are supplied with drugs
produced and consumed locally. Well-settled law controls
our answer. The CSA is a valid exercise of federal power,
even as applied to the troubling facts of this case. We
accordingly vacate the judgment of the Court of Appeals.
II
Shortly after taking office in 1969, President Nixon
declared a national “war on drugs.”9 As the first campaign
of that war, Congress set out to enact legislation that
would consolidate various drug laws on the books into a
comprehensive statute, provide meaningful regulation
over legitimate sources of drugs to prevent diversion into
illegal channels, and strengthen law enforcement tools
against the traffic in illicit drugs.10 That effort culminated
——————
9 See
D. Musto & P. Korsmeyer, The Quest for Drug Control 60 (2002)
(hereinafter Musto & Korsmeyer).
10 H. R. Rep. No. 91–1444, pt. 2, p. 22 (1970) (hereinafter H. R. Rep.);

26 Congressional Quarterly Almanac 531 (1970) (hereinafter Almanac);
 Cite as: 545 U. S. ____ (2005) 7

Opinion of the Court

in the passage of the Comprehensive Drug Abuse Preven-
tion and Control Act of 1970, 84 Stat. 1236.
This was not, however, Congress’ first attempt to regu-
late the national market in drugs. Rather, as early as
1906 Congress enacted federal legislation imposing label-
ing regulations on medications and prohibiting the manu-
facture or shipment of any adulterated or misbranded
drug traveling in interstate commerce.11 Aside from these
labeling restrictions, most domestic drug regulations prior
to 1970 generally came in the guise of revenue laws, with
the Department of the Treasury serving as the Federal
Government’s primary enforcer.12 For example, the pri-
mary drug control law, before being repealed by the pas-
sage of the CSA, was the Harrison Narcotics Act of 1914,
38 Stat. 785 (repealed 1970). The Harrison Act sought to
exert control over the possession and sale of narcotics,
specifically cocaine and opiates, by requiring producers,
distributors, and purchasers to register with the Federal
Government, by assessing taxes against parties so regis-
tered, and by regulating the issuance of prescriptions.13
Marijuana itself was not significantly regulated by the
Federal Government until 1937 when accounts of mari-
juana’s addictive qualities and physiological effects, paired
with dissatisfaction with enforcement efforts at state and
local levels, prompted Congress to pass the Marihuana
Tax Act, Pub. L. 75–238, 50 Stat. 551 (repealed 1970).14
——————
Musto & Korsmeyer 56–57.
11 Pure Food and Drug Act of 1906, ch. 3915, 34 Stat. 768, repealed by

Act of June 25, 1938, ch. 675, §902(a), 52 Stat. 1059.
12 See United States v. Doremus, 249 U. S. 86 (1919); Leary v. United

States, 395 U. S. 6, 14–16 (1969).
13 See Doremus, 249 U. S., at 90–93.
14 R. Bonnie & C. Whitebread, The Marijuana Conviction 154–174

(1999); L. Grinspoon & J. Bakalar, Marihuana, the Forbidden Medicine
7–8 (rev. ed. 1997) (hereinafter Grinspoon & Bakalar). Although this
was the Federal Government’s first attempt to regulate the marijuana
trade, by this time all States had in place some form of legislation
8 GONZALES v. RAICH

Opinion of the Court

Like the Harrison Act, the Marihuana Tax Act did not
outlaw the possession or sale of marijuana outright.
Rather, it imposed registration and reporting require-
ments for all individuals importing, producing, selling, or
dealing in marijuana, and required the payment of annual
taxes in addition to transfer taxes whenever the drug
changed hands.15 Moreover, doctors wishing to prescribe
marijuana for medical purposes were required to comply
with rather burdensome administrative requirements.16
Noncompliance exposed traffickers to severe federal penal-
ties, whereas compliance would often subject them to
prosecution under state law.17 Thus, while the Marihuana
Tax Act did not declare the drug illegal per se, the onerous
administrative requirements, the prohibitively expensive
taxes, and the risks attendant on compliance practically
curtailed the marijuana trade.
Then in 1970, after declaration of the national “war on
drugs,” federal drug policy underwent a significant trans-
formation. A number of noteworthy events precipitated
this policy shift. First, in Leary v. United States, 395 U. S.
6 (1969), this Court held certain provisions of the Marihu-
ana Tax Act and other narcotics legislation unconstitu-
tional. Second, at the end of his term, President Johnson
fundamentally reorganized the federal drug control agen-
cies. The Bureau of Narcotics, then housed in the De-
partment of Treasury, merged with the Bureau of Drug
Abuse Control, then housed in the Department of Health,
Education, and Welfare (HEW), to create the Bureau of
Narcotics and Dangerous Drugs, currently housed in the
Department of Justice.18 Finally, prompted by a perceived
——————
regulating the sale, use, or possession of marijuana. R. Isralowitz,
Drug Use, Policy, and Management 134 (2d ed. 2002).
15 Leary, 395 U. S., at 14–16.
16 Grinspoon & Bakalar 8.
17 Leary, 395 U. S., at 16–18.
18 Musto & Korsmeyer 32–35; 26 Almanac 533. In 1973, the Bureau
 Cite as: 545 U. S. ____ (2005) 9

Opinion of the Court

need to consolidate the growing number of piecemeal drug
laws and to enhance federal drug enforcement powers,
Congress enacted the Comprehensive Drug Abuse Preven-
tion and Control Act.19
Title II of that Act, the CSA, repealed most of the earlier
antidrug laws in favor of a comprehensive regime to com-
bat the international and interstate traffic in illicit drugs.
The main objectives of the CSA were to conquer drug
abuse and to control the legitimate and illegitimate traffic
in controlled substances.20 Congress was particularly
——————
of Narcotics and Dangerous Drugs became the Drug Enforcement
Administration (DEA). See Reorg. Plan No. 2 of 1973, §1, 28 CFR
§0.100 (1973).
19 The Comprehensive Drug Abuse Prevention and Control Act of

1970 consists of three titles. Title I relates to the prevention and
treatment of narcotic addicts through HEW (now the Department of
Health and Human Services). 84 Stat. 1238. Title II, as discussed in
more detail above, addresses drug control and enforcement as adminis-
tered by the Attorney General and the DEA. Id., at 1242. Title III
concerns the import and export of controlled substances. Id., at 1285.
20 In particular, Congress made the following findings:

“(1) Many of the drugs included within this subchapter have a useful
and legitimate medical purpose and are necessary to maintain the
health and general welfare of the American people.
“(2) The illegal importation, manufacture, distribution, and posses-
sion and improper use of controlled substances have a substantial and
detrimental effect on the health and general welfare of the American
people.
“(3) A major portion of the traffic in controlled substances flows
through interstate and foreign commerce. Incidents of the traffic which
are not an integral part of the interstate or foreign flow, such as manu-
facture, local distribution, and possession, nonetheless have a substan-
tial and direct effect upon interstate commerce because—
“(A) after manufacture, many controlled substances are trans-
ported in interstate commerce,
“(B) controlled substances distributed locally usually have been
transported in interstate commerce immediately before their distribu-
tion, and
“(C) controlled substances possessed commonly flow through
interstate commerce immediately prior to such possession.
10 GONZALES v. RAICH

Opinion of the Court

concerned with the need to prevent the diversion of drugs
from legitimate to illicit channels.21
To effectuate these goals, Congress devised a closed
regulatory system making it unlawful to manufacture,
distribute, dispense, or possess any controlled substance
except in a manner authorized by the CSA. 21 U. S. C.
§§841(a)(1), 844(a). The CSA categorizes all controlled
substances into five schedules. §812. The drugs are
grouped together based on their accepted medical uses,
the potential for abuse, and their psychological and physi-
cal effects on the body. §§811, 812. Each schedule is
associated with a distinct set of controls regarding the
manufacture, distribution, and use of the substances listed
therein. §§821–830. The CSA and its implementing
regulations set forth strict requirements regarding regis-
tration, labeling and packaging, production quotas, drug
security, and recordkeeping. Ibid. 21 CFR §1301 et seq.
(2004).
In enacting the CSA, Congress classified marijuana as a
Schedule I drug. 21 U. S. C. §812(c). This preliminary
classification was based, in part, on the recommendation
of the Assistant Secretary of HEW “that marihuana be
retained within schedule I at least until the completion of

——————
“(4) Local distribution and possession of controlled substances con-
tribute to swelling the interstate traffic in such substances.
“(5) Controlled substances manufactured and distributed intrastate
cannot be differentiated from controlled substances manufactured and
distributed interstate. Thus, it is not feasible to distinguish, in terms of
controls, between controlled substances manufactured and distributed
interstate and controlled substances manufactured and distributed
intrastate.
“(6) Federal control of the intrastate incidents of the traffic in con-
trolled substances is essential to the effective control of the interstate
incidents of such traffic.” 21 U. S. C. §§801(1)–(6).
21 See United States v. Moore, 423 U. S. 122, 135 (1975); see also H. R.

Rep., at 22.
 Cite as: 545 U. S. ____ (2005) 11

Opinion of the Court

certain studies now underway.”22 Schedule I drugs are
categorized as such because of their high potential for
abuse, lack of any accepted medical use, and absence of
any accepted safety for use in medically supervised treat-
ment. §812(b)(1). These three factors, in varying grada-
tions, are also used to categorize drugs in the other four
schedules. For example, Schedule II substances also have
a high potential for abuse which may lead to severe psy-
chological or physical dependence, but unlike Schedule I
drugs, they have a currently accepted medical use.
§812(b)(2). By classifying marijuana as a Schedule I drug,
as opposed to listing it on a lesser schedule, the manufac-
ture, distribution, or possession of marijuana became a
criminal offense, with the sole exception being use of the
drug as part of a Food and Drug Administration pre-
approved research study. §§823(f), 841(a)(1), 844(a); see
also United States v. Oakland Cannabis Buyers’ Coopera-
tive, 532 U. S. 483, 490 (2001).
The CSA provides for the periodic updating of schedules
and delegates authority to the Attorney General, after
consultation with the Secretary of Health and Human
Services, to add, remove, or transfer substances to, from,
or between schedules. §811. Despite considerable efforts
to reschedule marijuana, it remains a Schedule I drug.23
——————
22 H. R. Rep., at 61 (quoting letter from Roger E. Egeberg, M. D. to

Hon. Harley O. Staggers (Aug. 14, 1970)).
23 Starting in 1972, the National Organization for the Reform of Mari-

juana Laws (NORML) began its campaign to reclassify marijuana.
Grinspoon & Bakalar 13–17. After some fleeting success in 1988 when
an Administrative Law Judge (ALJ) declared that the DEA would be
acting in an “unreasonable, arbitrary, and capricious” manner if it
continued to deny marijuana access to seriously ill patients, and
concluded that it should be reclassified as a Schedule III substance,
Grinspoon v. DEA, 828 F. 2d 881, 883–884 (CA1 1987), the campaign
has proved unsuccessful. The DEA Administrator did not endorse the
ALJ’s findings, 54 Fed. Reg. 53767 (1989), and since that time has
routinely denied petitions to reschedule the drug, most recently in
12 GONZALES v. RAICH

Opinion of the Court

III
Respondents in this case do not dispute that passage of
the CSA, as part of the Comprehensive Drug Abuse Pre-
vention and Control Act, was well within Congress’ com-
merce power. Brief for Respondents 22, 38. Nor do they
contend that any provision or section of the CSA amounts
to an unconstitutional exercise of congressional authority.
Rather, respondents’ challenge is actually quite limited;
they argue that the CSA’s categorical prohibition of the
manufacture and possession of marijuana as applied to
the intrastate manufacture and possession of marijuana
for medical purposes pursuant to California law exceeds
Congress’ authority under the Commerce Clause.
In assessing the validity of congressional regulation,
none of our Commerce Clause cases can be viewed in
isolation. As charted in considerable detail in United
States v. Lopez, our understanding of the reach of the
Commerce Clause, as well as Congress’ assertion of au-
thority thereunder, has evolved over time.24 The Com-
merce Clause emerged as the Framers’ response to the
central problem giving rise to the Constitution itself: the
absence of any federal commerce power under the Articles
of Confederation.25 For the first century of our history, the
primary use of the Clause was to preclude the kind of
discriminatory state legislation that had once been per-

——————
2001. 66 Fed. Reg. 20038 (2001). The Court of Appeals for the District
of Columbia Circuit has reviewed the petition to reschedule marijuana
on five separate occasions over the course of 30 years, ultimately
upholding the Administrator’s final order. See Alliance for Cannabis
Therapeutics v. DEA, 15 F. 3d 1131, 1133 (1994).
24 United States v. Lopez, 514 U. S. 549, 552–558 (1995); id., at 568–574

(KENNEDY, J., concurring); id., at 604–607 (SOUTER, J., dissenting).
25 See Gibbons v. Ogden, 9 Wheat. 1, 224 (1824) (opinion of Johnson, J.);

Stern, That Commerce Which Concerns More States Than One, 47 Harv.
L. Rev. 1335, 1337, 1340–1341 (1934); G. Gunther, Constitutional Law
127 (9th ed. 1975).
 Cite as: 545 U. S. ____ (2005) 13

Opinion of the Court

missible.26 Then, in response to rapid industrial develop-
ment and an increasingly interdependent national econ-
omy, Congress “ushered in a new era of federal regulation
under the commerce power,” beginning with the enact-
ment of the Interstate Commerce Act in 1887, 24 Stat.
379, and the Sherman Antitrust Act in 1890, 26 Stat. 209,
as amended, 15 U. S. C. §2 et seq.27
Cases decided during that “new era,” which now spans
more than a century, have identified three general catego-
ries of regulation in which Congress is authorized to en-
gage under its commerce power. First, Congress can
regulate the channels of interstate commerce. Perez v.
United States, 402 U. S. 146, 150 (1971). Second, Congress
has authority to regulate and protect the instrumentalities
of interstate commerce, and persons or things in interstate
commerce. Ibid. Third, Congress has the power to regu-
late activities that substantially affect interstate com-
merce. Ibid.; NLRB v. Jones & Laughlin Steel Corp., 301
U. S. 1, 37 (1937). Only the third category is implicated in
the case at hand.
Our case law firmly establishes Congress’ power to
regulate purely local activities that are part of an eco-
nomic “class of activities” that have a substantial effect on
interstate commerce. See, e.g., Perez, 402 U. S., at 151;
——————
26 See Lopez, 514 U. S., at 553–554; id., at 568–569 (KENNEDY, J.,

concurring); see also Granholm v. Heald, 544 U. S. __, __ (2005) (slip
op., at 8–9).
27 Lopez, 514 U. S., at 554; see also Wickard v. Filburn, 317 U. S.

111, 121 (1942) (“It was not until 1887, with the enactment of the
Interstate Commerce Act, that the interstate commerce power began
to exert positive influence in American law and life. This first impor-
tant federal resort to the commerce power was followed in 1890 by the
Sherman Anti-Trust Act and, thereafter, mainly after 1903, by many
others. These statutes ushered in new phases of adjudication, which
required the Court to approach the interpretation of the Commerce
Clause in the light of an actual exercise by Congress of its power
thereunder” (footnotes omitted)).
14 GONZALES v. RAICH

Opinion of the Court

Wickard v. Filburn, 317 U. S. 111, 128–129 (1942). As we
stated in Wickard, “even if appellee’s activity be local and
though it may not be regarded as commerce, it may still,
whatever its nature, be reached by Congress if it exerts a
substantial economic effect on interstate commerce.” Id.,
at 125. We have never required Congress to legislate with
scientific exactitude. When Congress decides that the
“ ‘total incidence’ ” of a practice poses a threat to a national
market, it may regulate the entire class. See Perez, 402
U. S., at 154–155 (quoting Westfall v. United States, 274
U. S. 256, 259 (1927) (“[W]hen it is necessary in order to
prevent an evil to make the law embrace more than the
precise thing to be prevented it may do so”)). In this vein,
we have reiterated that when “‘a general regulatory statute
bears a substantial relation to commerce, the de minimis
character of individual instances arising under that statute
is of no consequence.’” E.g., Lopez, 514 U. S., at 558 (em-
phasis deleted) (quoting Maryland v. Wirtz, 392 U. S. 183,
196, n. 27 (1968)).
Our decision in Wickard, 317 U. S. 111, is of particular
relevance. In Wickard, we upheld the application of regu-
lations promulgated under the Agricultural Adjustment
Act of 1938, 52 Stat. 31, which were designed to control
the volume of wheat moving in interstate and foreign
commerce in order to avoid surpluses and consequent
abnormally low prices. The regulations established an
allotment of 11.1 acres for Filburn’s 1941 wheat crop, but
he sowed 23 acres, intending to use the excess by consum-
ing it on his own farm. Filburn argued that even though
we had sustained Congress’ power to regulate the produc-
tion of goods for commerce, that power did not authorize
“federal regulation [of] production not intended in any
part for commerce but wholly for consumption on the
farm.” Wickard, 317 U. S., at 118. Justice Jackson’s
opinion for a unanimous Court rejected this submission.
He wrote:
 Cite as: 545 U. S. ____ (2005) 15

Opinion of the Court

“The effect of the statute before us is to restrict the
amount which may be produced for market and the
extent as well to which one may forestall resort to the
market by producing to meet his own needs. That ap-
pellee’s own contribution to the demand for wheat
may be trivial by itself is not enough to remove him
from the scope of federal regulation where, as here,
his contribution, taken together with that of many
others similarly situated, is far from trivial.” Id., at
127–128.
Wickard thus establishes that Congress can regulate
purely intrastate activity that is not itself “commercial,” in
that it is not produced for sale, if it concludes that failure
to regulate that class of activity would undercut the regu-
lation of the interstate market in that commodity.
The similarities between this case and Wickard are
striking. Like the farmer in Wickard, respondents are
cultivating, for home consumption, a fungible commodity
for which there is an established, albeit illegal, interstate
market.28 Just as the Agricultural Adjustment Act was
designed “to control the volume [of wheat] moving in
interstate and foreign commerce in order to avoid sur-
pluses . . .” and consequently control the market price,
id., at 115, a primary purpose of the CSA is to control the
supply and demand of controlled substances in both
lawful and unlawful drug markets. See nn. 20–21, supra.
——————
28 Even respondents acknowledge the existence of an illicit market in

marijuana; indeed, Raich has personally participated in that market,
and Monson expresses a willingness to do so in the future. App. 59, 74,
87. See also Department of Revenue of Mont. v. Kurth Ranch, 511 U. S.
767, 770, 774, n. 12, and 780, n. 17 (1994) (discussing the “market
value” of marijuana); id., at 790 (REHNQUIST, C. J., dissenting); id., at
792 (O’CONNOR, J., dissenting); Whalen v. Roe, 429 U. S. 589, 591
(1977) (addressing prescription drugs “for which there is both a lawful
and an unlawful market”); Turner v. United States, 396 U. S. 398, 417,
n. 33 (1970) (referring to the purchase of drugs on the “retail market”).
16 GONZALES v. RAICH

Opinion of the Court

In Wickard, we had no difficulty concluding that Con-
gress had a rational basis for believing that, when viewed
in the aggregate, leaving home-consumed wheat outside
the regulatory scheme would have a substantial influence
on price and market conditions. Here too, Congress had
a rational basis for concluding that leaving home-
consumed marijuana outside federal control would simi-
larly affect price and market conditions.
More concretely, one concern prompting inclusion of
wheat grown for home consumption in the 1938 Act was
that rising market prices could draw such wheat into the
interstate market, resulting in lower market prices.
Wickard, 317 U. S., at 128. The parallel concern making it
appropriate to include marijuana grown for home con-
sumption in the CSA is the likelihood that the high de-
mand in the interstate market will draw such marijuana
into that market. While the diversion of homegrown
wheat tended to frustrate the federal interest in stabiliz-
ing prices by regulating the volume of commercial transac-
tions in the interstate market, the diversion of homegrown
marijuana tends to frustrate the federal interest in elimi-
nating commercial transactions in the interstate market
in their entirety. In both cases, the regulation is squarely
within Congress’ commerce power because production of
the commodity meant for home consumption, be it wheat
or marijuana, has a substantial effect on supply and de-
mand in the national market for that commodity.29
——————
29 To be sure, the wheat market is a lawful market that Congress

sought to protect and stabilize, whereas the marijuana market is an
unlawful market that Congress sought to eradicate. This difference,
however, is of no constitutional import. It has long been settled that
Congress’ power to regulate commerce includes the power to prohibit
commerce in a particular commodity. Lopez, 514 U. S., at 571 (KENNEDY,
J., concurring) (“In the Lottery Case, 188 U. S. 321 (1903), the Court
rejected the argument that Congress lacked [the] power to prohibit the
interstate movement of lottery tickets because it had power only to
regulate, not to prohibit”); see also Wickard, 317 U. S., at 128 (“The
 Cite as: 545 U. S. ____ (2005) 17

Opinion of the Court

Nonetheless, respondents suggest that Wickard differs
from this case in three respects: (1) the Agricultural Ad-
justment Act, unlike the CSA, exempted small farming
operations; (2) Wickard involved a “quintessential eco-
nomic activity”—a commercial farm—whereas respon-
dents do not sell marijuana; and (3) the Wickard record
made it clear that the aggregate production of wheat for
use on farms had a significant impact on market prices.
Those differences, though factually accurate, do not dimin-
ish the precedential force of this Court’s reasoning.
The fact that Wickard’s own impact on the market was
“trivial by itself ” was not a sufficient reason for removing
him from the scope of federal regulation. 317 U. S., at
127. That the Secretary of Agriculture elected to exempt
even smaller farms from regulation does not speak to his
power to regulate all those whose aggregated production
was significant, nor did that fact play any role in the
Court’s analysis. Moreover, even though Wickard was
indeed a commercial farmer, the activity he was engaged
in—the cultivation of wheat for home consumption—was
not treated by the Court as part of his commercial farming
operation.30 And while it is true that the record in the
Wickard case itself established the causal connection
between the production for local use and the national
market, we have before us findings by Congress to the
same effect.
Findings in the introductory sections of the CSA explain
why Congress deemed it appropriate to encompass local
activities within the scope of the CSA. See n. 20, supra.
The submissions of the parties and the numerous amici all
seem to agree that the national, and international, market

——————
stimulation of commerce is a use of the regulatory function quite as
definitely as prohibitions or restrictions thereon”).
30 See Wickard, 317 U. S., at 125 (recognizing that Wickard’s activity

“may not be regarded as commerce”).
18 GONZALES v. RAICH

Opinion of the Court

for marijuana has dimensions that are fully comparable to
those defining the class of activities regulated by the
Secretary pursuant to the 1938 statute.31 Respondents
nonetheless insist that the CSA cannot be constitutionally
applied to their activities because Congress did not make a
specific finding that the intrastate cultivation and posses-
sion of marijuana for medical purposes based on the rec-
ommendation of a physician would substantially affect the
larger interstate marijuana market. Be that as it may, we
have never required Congress to make particularized
findings in order to legislate, see Lopez, 514 U. S., at 562;
Perez, 402 U. S., at 156, absent a special concern such as
the protection of free speech, see, e.g., Turner Broadcast-
ing System, Inc. v. FCC, 512 U. S. 622, 664–668 (1994)
(plurality opinion). While congressional findings are
certainly helpful in reviewing the substance of a congres-
sional statutory scheme, particularly when the connection
to commerce is not self-evident, and while we will consider
congressional findings in our analysis when they are
available, the absence of particularized findings does not
call into question Congress’ authority to legislate.32
——————
31 The Executive Office of the President has estimated that in 2000

American users spent $10.5 billion on the purchase of marijuana. Office of
Nat. Drug Control Policy, Marijuana Fact Sheet 5 (Feb. 2004), available at
http://www.whitehousedrugpolicy.gov/publications/factsht/marijuana/index
.html (all Internet materials as visited June 2, 2005, and available in Clerk
of Court’s case file).
32 Moreover, as discussed in more detail above, Congress did make

findings regarding the effects of intrastate drug activity on interstate
commerce. See n. 20, supra. Indeed, even the Court of Appeals found
that those findings “weigh[ed] in favor” of upholding the constitutional-
ity of the CSA. 352 F. 3d 1222, 1232 (CA9 2003) (case below). The
dissenters, however, would impose a new and heightened burden on
Congress (unless the litigants can garner evidence sufficient to cure
Congress’ perceived “inadequa[cies]”)—that legislation must contain
detailed findings proving that each activity regulated within a compre-
hensive statute is essential to the statutory scheme. Post, at 13–15
(O’CONNOR, J., dissenting); post, at 8 (THOMAS, J., dissenting). Such an
 Cite as: 545 U. S. ____ (2005) 19

Opinion of the Court

In assessing the scope of Congress’ authority under the
Commerce Clause, we stress that the task before us is a
modest one. We need not determine whether respondents’
activities, taken in the aggregate, substantially affect
interstate commerce in fact, but only whether a “rational
basis” exists for so concluding. Lopez, 514 U. S., at 557;
see also Hodel v. Virginia Surface Mining & Reclamation
Assn., Inc., 452 U. S. 264, 276–280 (1981); Perez, 402 U. S.,
at 155–156; Katzenbach v. McClung, 379 U. S. 294, 299–
301 (1964); Heart of Atlanta Motel, Inc. v. United States,
379 U. S. 241, 252–253 (1964). Given the enforcement
difficulties that attend distinguishing between marijuana
cultivated locally and marijuana grown elsewhere, 21
U. S. C. §801(5), and concerns about diversion into illicit
channels,33 we have no difficulty concluding that Congress
had a rational basis for believing that failure to regulate
the intrastate manufacture and possession of marijuana
would leave a gaping hole in the CSA. Thus, as in
Wickard, when it enacted comprehensive legislation to
regulate the interstate market in a fungible commodity,
Congress was acting well within its authority to “make all
Laws which shall be necessary and proper” to “regulate
Commerce . . . among the several States.” U. S. Const.,
Art. I, §8. That the regulation ensnares some purely
intrastate activity is of no moment. As we have done
many times before, we refuse to excise individual compo-
——————
exacting requirement is not only unprecedented, it is also impractical.
Indeed, the principal dissent’s critique of Congress for “not even”
including “declarations” specific to marijuana is particularly unpersua-
sive given that the CSA initially identified 80 other substances subject
to regulation as Schedule I drugs, not to mention those categorized in
Schedules II–V. Post, at 14 (O’CONNOR, J., dissenting). Surely, Con-
gress cannot be expected (and certainly should not be required) to
include specific findings on each and every substance contained therein
in order to satisfy the dissenters’ unfounded skepticism.
33 See n. 21, supra (citing sources that evince Congress’ particular

concern with the diversion of drugs from legitimate to illicit channels).
20 GONZALES v. RAICH

Opinion of the Court

nents of that larger scheme.
IV
To support their contrary submission, respondents rely
heavily on two of our more recent Commerce Clause cases.
In their myopic focus, they overlook the larger context of
modern-era Commerce Clause jurisprudence preserved by
those cases. Moreover, even in the narrow prism of re-
spondents’ creation, they read those cases far too broadly.
Those two cases, of course, are Lopez, 514 U. S. 549, and
Morrison, 529 U. S. 598. As an initial matter, the statu-
tory challenges at issue in those cases were markedly
different from the challenge respondents pursue in the
case at hand. Here, respondents ask us to excise individ-
ual applications of a concededly valid statutory scheme.
In contrast, in both Lopez and Morrison, the parties as-
serted that a particular statute or provision fell outside
Congress’ commerce power in its entirety. This distinction
is pivotal for we have often reiterated that “[w]here the
class of activities is regulated and that class is within the
reach of federal power, the courts have no power ‘to excise,
as trivial, individual instances’ of the class.” Perez, 402
U. S., at 154 (emphasis deleted) (quoting Wirtz, 392 U. S.,
at 193); see also Hodel, 452 U. S., at 308.
At issue in Lopez, 514 U. S. 549, was the validity of the
Gun-Free School Zones Act of 1990, which was a brief,
single-subject statute making it a crime for an individual to
possess a gun in a school zone. 104 Stat. 4844–4845, 18
U. S. C. §922(q)(1)(A). The Act did not regulate any eco-
nomic activity and did not contain any requirement that
the possession of a gun have any connection to past inter-
state activity or a predictable impact on future commercial
activity. Distinguishing our earlier cases holding that
comprehensive regulatory statutes may be validly applied
to local conduct that does not, when viewed in isolation,
have a significant impact on interstate commerce, we held
 Cite as: 545 U. S. ____ (2005) 21

Opinion of the Court

the statute invalid. We explained:
“Section 922(q) is a criminal statute that by its terms
has nothing to do with ‘commerce’ or any sort of eco-
nomic enterprise, however broadly one might define
those terms. Section 922(q) is not an essential part of
a larger regulation of economic activity, in which the
regulatory scheme could be undercut unless the intra-
state activity were regulated. It cannot, therefore, be
sustained under our cases upholding regulations of
activities that arise out of or are connected with a
commercial transaction, which viewed in the aggre-
gate, substantially affects interstate commerce.” 514
U. S., at 561.
The statutory scheme that the Government is defending
in this litigation is at the opposite end of the regulatory
spectrum. As explained above, the CSA, enacted in 1970
as part of the Comprehensive Drug Abuse Prevention and
Control Act, 84 Stat. 1242–1284, was a lengthy and de-
tailed statute creating a comprehensive framework for
regulating the production, distribution, and possession of
five classes of “controlled substances.” Most of those
substances—those listed in Schedules II through V—“have
a useful and legitimate medical purpose and are necessary
to maintain the health and general welfare of the Ameri-
can people.” 21 U. S. C. §801(1). The regulatory scheme
is designed to foster the beneficial use of those medica-
tions, to prevent their misuse, and to prohibit entirely the
possession or use of substances listed in Schedule I, except
as a part of a strictly controlled research project.
While the statute provided for the periodic updating of
the five schedules, Congress itself made the initial classifi-
cations. It identified 42 opiates, 22 opium derivatives, and
17 hallucinogenic substances as Schedule I drugs. 84 Stat.
1248. Marijuana was listed as the 10th item in the third
subcategory. That classification, unlike the discrete pro-
22 GONZALES v. RAICH

Opinion of the Court

hibition established by the Gun-Free School Zones Act of
1990, was merely one of many “essential part[s] of a larger
regulation of economic activity, in which the regulatory
scheme could be undercut unless the intrastate activity
were regulated.” Lopez, 514 U. S., at 561.34 Our opinion
in Lopez casts no doubt on the validity of such a program.
Nor does this Court’s holding in Morrison, 529 U. S. 598.
The Violence Against Women Act of 1994, 108 Stat. 1902,
created a federal civil remedy for the victims of gender-
motivated crimes of violence. 42 U. S. C. §13981. The
remedy was enforceable in both state and federal courts,
and generally depended on proof of the violation of a state
law. Despite congressional findings that such crimes had
an adverse impact on interstate commerce, we held the
statute unconstitutional because, like the statute in Lopez,
it did not regulate economic activity. We concluded that
“the noneconomic, criminal nature of the conduct at issue
was central to our decision” in Lopez, and that our prior
cases had identified a clear pattern of analysis: “ ‘Where
economic activity substantially affects interstate com-
merce, legislation regulating that activity will be sus-
tained.’ ”35 Morrison, 529 U. S., at 610.
Unlike those at issue in Lopez and Morrison, the activi-
——————
34 The principal dissent asserts that by “[s]eizing upon our language
in Lopez,” post, at 5 (opinion of O’CONNOR, J.), i.e., giving effect to our
well-established case law, Congress will now have an incentive to
legislate broadly. Even putting aside the political checks that would
generally curb Congress’ power to enact a broad and comprehensive
scheme for the purpose of targeting purely local activity, there is no
suggestion that the CSA constitutes the type of “evasive” legislation the
dissent fears, nor could such an argument plausibly be made. Post, at 6
(O’CONNOR, J., dissenting).
35 Lopez, 514 U. S., at 560; see also id., at 573–574 (KENNEDY, J., con-

curring) (stating that Lopez did not alter our “practical conception of
commercial regulation” and that Congress may “regulate in the com-
mercial sphere on the assumption that we have a single market and a
unified purpose to build a stable national economy”).
 Cite as: 545 U. S. ____ (2005) 23

Opinion of the Court

ties regulated by the CSA are quintessentially economic.
“Economics” refers to “the production, distribution, and
consumption of commodities.” Webster’s Third New In-
ternational Dictionary 720 (1966). The CSA is a statute
that regulates the production, distribution, and consump-
tion of commodities for which there is an established, and
lucrative, interstate market. Prohibiting the intrastate
possession or manufacture of an article of commerce is a
rational (and commonly utilized) means of regulating
commerce in that product.36 Such prohibitions include
specific decisions requiring that a drug be withdrawn from
the market as a result of the failure to comply with regula-
tory requirements as well as decisions excluding Schedule
I drugs entirely from the market. Because the CSA is a
statute that directly regulates economic, commercial
activity, our opinion in Morrison casts no doubt on its
constitutionality.
The Court of Appeals was able to conclude otherwise
only by isolating a “separate and distinct” class of activi-
ties that it held to be beyond the reach of federal power,
defined as “the intrastate, noncommercial cultivation,
possession and use of marijuana for personal medical
purposes on the advice of a physician and in accordance
with state law.” 352 F. 3d, at 1229. The court character-
ized this class as “different in kind from drug trafficking.”
Id., at 1228. The differences between the members of a
class so defined and the principal traffickers in Schedule I
substances might be sufficient to justify a policy decision
exempting the narrower class from the coverage of the
CSA. The question, however, is whether Congress’ con-
trary policy judgment, i.e., its decision to include this
narrower “class of activities” within the larger regulatory
——————
36 See 16 U. S. C. §668(a) (bald and golden eagles); 18 U. S. C. §175(a)

(biological weapons); §831(a) (nuclear material); §842(n)(1) (certain
plastic explosives); §2342(a) (contraband cigarettes).
24 GONZALES v. RAICH

Opinion of the Court

scheme, was constitutionally deficient. We have no diffi-
culty concluding that Congress acted rationally in deter-
mining that none of the characteristics making up the
purported class, whether viewed individually or in the
aggregate, compelled an exemption from the CSA; rather,
the subdivided class of activities defined by the Court of
Appeals was an essential part of the larger regulatory
scheme.
First, the fact that marijuana is used “for personal
medical purposes on the advice of a physician” cannot
itself serve as a distinguishing factor. 352 F. 3d, at 1229.
The CSA designates marijuana as contraband for any
purpose; in fact, by characterizing marijuana as a Sched-
ule I drug, Congress expressly found that the drug has no
acceptable medical uses. Moreover, the CSA is a compre-
hensive regulatory regime specifically designed to regulate
which controlled substances can be utilized for medicinal
purposes, and in what manner. Indeed, most of the sub-
stances classified in the CSA “have a useful and legitimate
medical purpose.” 21 U. S. C. §801(1). Thus, even if
respondents are correct that marijuana does have ac-
cepted medical uses and thus should be redesignated as a
lesser schedule drug,37 the CSA would still impose controls
——————
37 We acknowledge that evidence proffered by respondents in this case
regarding the effective medical uses for marijuana, if found credible
after trial, would cast serious doubt on the accuracy of the findings that
require marijuana to be listed in Schedule I. See, e.g., Institute of
Medicine, Marijuana and Medicine: Assessing the Science Base 179 (J.
Joy, S. Watson, & J. Benson eds. 1999) (recognizing that “[s]cientific
data indicate the potential therapeutic value of cannabinoid drugs,
primarily THC [Tetrahydrocannabinol] for pain relief, control of nausea
and vomiting, and appetite stimulation”); see also Conant v. Walters,
309 F. 3d 629, 640–643 (CA9 2002) (Kozinski, J., concurring) (chroni-
cling medical studies recognizing valid medical uses for marijuana and
its derivatives). But the possibility that the drug may be reclassified in
the future has no relevance to the question whether Congress now has
the power to regulate its production and distribution. Respondents’
 Cite as: 545 U. S. ____ (2005) 25

Opinion of the Court

beyond what is required by California law. The CSA
requires manufacturers, physicians, pharmacies, and
other handlers of controlled substances to comply with
statutory and regulatory provisions mandating registra-
tion with the DEA, compliance with specific production
quotas, security controls to guard against diversion, re-
cordkeeping and reporting obligations, and prescription
requirements. See 21 U. S. C. §§821–830; 21 CFR §1301 et
seq. (2004). Furthermore, the dispensing of new drugs,
even when doctors approve their use, must await federal
approval. United States v. Rutherford, 442 U. S. 544
(1979). Accordingly, the mere fact that marijuana—like
virtually every other controlled substance regulated by the
CSA—is used for medicinal purposes cannot possibly serve
to distinguish it from the core activities regulated by the
CSA.
Nor can it serve as an “objective marke[r]” or “objective
facto[r]” to arbitrarily narrow the relevant class as the
dissenters suggest, post, at 6 (O’CONNOR, J., dissenting);
post, at 12 (THOMAS, J., dissenting). More fundamentally,
if, as the principal dissent contends, the personal cultiva-
tion, possession, and use of marijuana for medicinal pur-
poses is beyond the “ ‘outer limits’ of Congress’ Commerce
Clause authority,” post, at 1 (O’CONNOR, J., dissenting), it
must also be true that such personal use of marijuana (or
any other homegrown drug) for recreational purposes is
also beyond those “ ‘outer limits,’ ” whether or not a State
elects to authorize or even regulate such use. JUSTICE
THOMAS’ separate dissent suffers from the same sweeping
implications. That is, the dissenters’ rationale logically
extends to place any federal regulation (including quality,
prescription, or quantity controls) of any locally cultivated
and possessed controlled substance for any purpose be-
——————

submission, if accepted, would place all homegrown medical substances

beyond the reach of Congress’ regulatory jurisdiction.

26 GONZALES v. RAICH

Opinion of the Court

yond the “ ‘outer limits’ ” of Congress’ Commerce Clause
authority. One need not have a degree in economics to
understand why a nationwide exemption for the vast
quantity of marijuana (or other drugs) locally cultivated
for personal use (which presumably would include use by
friends, neighbors, and family members) may have a
substantial impact on the interstate market for this ex-
traordinarily popular substance. The congressional judg-
ment that an exemption for such a significant segment of
the total market would undermine the orderly enforce-
ment of the entire regulatory scheme is entitled to a
strong presumption of validity. Indeed, that judgment is
not only rational, but “visible to the naked eye,” Lopez, 514
U. S., at 563, under any commonsense appraisal of the
probable consequences of such an open-ended exemption.
Second, limiting the activity to marijuana possession
and cultivation “in accordance with state law” cannot
serve to place respondents’ activities beyond congressional
reach. The Supremacy Clause unambiguously provides
that if there is any conflict between federal and state law,
federal law shall prevail. It is beyond peradventure that
federal power over commerce is “ ‘superior to that of the
States to provide for the welfare or necessities of their
inhabitants,’ ” however legitimate or dire those necessities
may be. Wirtz, 392 U. S., at 196 (quoting Sanitary Dist. of
Chicago v. United States, 266 U. S. 405, 426 (1925)). See
also 392 U. S., at 195–196; Wickard, 317 U. S., at 124
(“ ‘[N]o form of state activity can constitutionally thwart
the regulatory power granted by the commerce clause to
Congress’ ”). Just as state acquiescence to federal regula-
tion cannot expand the bounds of the Commerce Clause,
see, e.g., Morrison, 529 U. S., at 661–662 (BREYER, J.,
dissenting) (noting that 38 States requested federal inter-
vention), so too state action cannot circumscribe Congress’
plenary commerce power. See United States v. Darby, 312
U. S. 100, 114 (1941) (“That power can neither be enlarged
 Cite as: 545 U. S. ____ (2005) 27

Opinion of the Court

nor diminished by the exercise or non-exercise of state
power”).38
Respondents acknowledge this proposition, but nonethe-
less contend that their activities were not “an essential
part of a larger regulatory scheme” because they had been
“isolated by the State of California, and [are] policed by
the State of California,” and thus remain “entirely sepa-
rated from the market.” Tr. of Oral Arg. 27. The dissent-
ers fall prey to similar reasoning. See n. 38, supra this
page. The notion that California law has surgically ex-
——————
38 That is so even if California’s current controls (enacted eight years

after the Compassionate Use Act was passed) are “[e]ffective,” as the
dissenters would have us blindly presume, post, at 15 (O’CONNOR, J.,
dissenting); post, at 6, 12 (THOMAS, J., dissenting). California’s decision
(made 34 years after the CSA was enacted) to impose “stric[t] controls”
on the “cultivation and possession of marijuana for medical purposes,”
post, at 6 (THOMAS, J., dissenting), cannot retroactively divest Congress
of its authority under the Commerce Clause. Indeed, JUSTICE THOMAS’
urgings to the contrary would turn the Supremacy Clause on its head,
and would resurrect limits on congressional power that have long since
been rejected. See post, at 8 (SCALIA, J., concurring in judgment)
(quoting McCulloch v. Maryland, 4 Wheat. 316, 424 (1819)) (“ ‘To impose
on [Congress] the necessity of resorting to means which it cannot control,
which another government may furnish or withhold, would render its
course precarious, the result of its measures uncertain, and create a
dependence on other governments, which might disappoint its most
important designs, and is incompatible with the language of the constitu-
tion’ ”).
Moreover, in addition to casting aside more than a century of this
Court’s Commerce Clause jurisprudence, it is noteworthy that JUSTICE
THOMAS’ suggestion that States possess the power to dictate the extent of
Congress’ commerce power would have far-reaching implications beyond
the facts of this case. For example, under his reasoning, Congress would
be equally powerless to regulate, let alone prohibit, the intrastate
possession, cultivation, and use of marijuana for recreational purposes,
an activity which all States “strictly contro[l].” Indeed, his rationale
seemingly would require Congress to cede its constitutional power to
regulate commerce whenever a State opts to exercise its “traditional
police powers to define the criminal law and to protect the health,
safety, and welfare of their citizens.” Post, at 9–10 (dissenting opinion).
28 GONZALES v. RAICH

Opinion of the Court

cised a discrete activity that is hermetically sealed off
from the larger interstate marijuana market is a dubious
proposition, and, more importantly, one that Congress
could have rationally rejected.
Indeed, that the California exemptions will have a sig-
nificant impact on both the supply and demand sides of
the market for marijuana is not just “plausible” as the
principal dissent concedes, post, at 16 (O’CONNOR, J.,
dissenting), it is readily apparent. The exemption for
physicians provides them with an economic incentive to
grant their patients permission to use the drug. In contrast
to most prescriptions for legal drugs, which limit the dosage
and duration of the usage, under California law the doctor’s
permission to recommend marijuana use is open-ended.
The authority to grant permission whenever the doctor
determines that a patient is afflicted with “any other illness
for which marijuana provides relief,” Cal. Health & Safety
Code Ann. §11362.5(b)(1)(A) (West Supp. 2005), is broad
enough to allow even the most scrupulous doctor to conclude
that some recreational uses would be therapeutic.39 And
our cases have taught us that there are some unscrupulous
physicians who overprescribe when it is sufficiently profit-
able to do so.40
The exemption for cultivation by patients and caregivers
can only increase the supply of marijuana in the California
market.41 The likelihood that all such production will
——————
39 California’s Compassionate Use Act has since been amended, limit-

ing the catchall category to “[a]ny other chronic or persistent medical
symptom that either: . . . [s]ubstantially limits the ability of the person
to conduct one or more major life activities as defined” in the Americans
with Disabilities Act of 1990, or “[i]f not alleviated, may cause serious
harm to the patient’s safety or physical or mental health.” Cal. Health
& Safety Code Ann. §§11362.7(h)(12)(A) to (12)(B) (West Supp. 2005).
40 See, e.g., United States v. Moore, 423 U. S. 122 (1975); United States

v. Doremus, 249 U. S. 86 (1919).
41 The state policy allows patients to possess up to eight ounces of
 Cite as: 545 U. S. ____ (2005) 29

Opinion of the Court

promptly terminate when patients recover or will precisely
match the patients’ medical needs during their convales-
cence seems remote; whereas the danger that excesses will
satisfy some of the admittedly enormous demand for recrea-
tional use seems obvious.42 Moreover, that the national and
international narcotics trade has thrived in the face of
vigorous criminal enforcement efforts suggests that no small
number of unscrupulous people will make use of the Cali-
fornia exemptions to serve their commercial ends whenever
it is feasible to do so.43 Taking into account the fact that
——————
dried marijuana, and to cultivate up to 6 mature or 12 immature
plants. Cal. Health & Safety Code Ann. §11362.77(a) (West Supp.
2005). However, the quantity limitations serve only as a floor. Based
on a doctor’s recommendation, a patient can possess whatever quantity
is necessary to satisfy his medical needs, and cities and counties are
given carte blanche to establish more generous limits. Indeed, several
cities and counties have done just that. For example, patients residing
in the cities of Oakland and Santa Cruz and in the counties of Sonoma
and Tehama are permitted to possess up to 3 pounds of processed
marijuana. Reply Brief for United States 19 (citing Proposition 215
Enforcement Guidelines). Putting that quantity in perspective, 3
pounds of marijuana yields roughly 3,000 joints or cigarettes. Execu-
tive Office of the President, Office of National Drug Control Policy,
What America’s Users Spend on Illegal Drugs 24 (Dec. 2001),
http://www.whitehousedrugpolicy.gov/publications/pdf/american_users_
spend_2002.pdf. And the street price for that amount can range
anywhere from $900 to $24,000. DEA, Illegal Drug Price and Purity
Report (Apr. 2003) (DEA–02058).
42 For example, respondent Raich attests that she uses 2.5 ounces of

cannabis a week. App. 82. Yet as a resident of Oakland, she is entitled
to possess up to 3 pounds of processed marijuana at any given time,
nearly 20 times more than she uses on a weekly basis.
43 See, e.g., People ex rel. Lungren v. Peron, 59 Cal. App. 4th 1383,

1386–1387 (1997) (recounting how a Cannabis Buyers’ Club engaged in
an “indiscriminate and uncontrolled pattern of sale to thousands of
persons among the general public, including persons who had not
demonstrated any recommendation or approval of a physician and, in
fact, some of whom were not under the care of a physician, such as
undercover officers,” and noting that “some persons who had purchased
marijuana on respondents’ premises were reselling it unlawfully on the
30 GONZALES v. RAICH

Opinion of the Court

California is only one of at least nine States to have author-
ized the medical use of marijuana, a fact JUSTICE
O’CONNOR’s dissent conveniently disregards in arguing that
the demonstrated effect on commerce while admittedly
“plausible” is ultimately “unsubstantiated,” post, at 14, 16,
Congress could have rationally concluded that the aggre-
gate impact on the national market of all the transactions
exempted from federal supervision is unquestionably
substantial.
So, from the “separate and distinct” class of activities
identified by the Court of Appeals (and adopted by the
dissenters), we are left with “the intrastate, noncommer-
cial cultivation, possession and use of marijuana.” 352
F. 3d, at 1229. Thus the case for the exemption comes
down to the claim that a locally cultivated product that is
used domestically rather than sold on the open market is
not subject to federal regulation. Given the findings in the
CSA and the undisputed magnitude of the commercial
market for marijuana, our decisions in Wickard v. Filburn
and the later cases endorsing its reasoning foreclose that
claim.
V
Respondents also raise a substantive due process claim
and seek to avail themselves of the medical necessity
defense. These theories of relief were set forth in their
complaint but were not reached by the Court of Appeals.
We therefore do not address the question whether judicial
relief is available to respondents on these alternative
bases. We do note, however, the presence of another
avenue of relief. As the Solicitor General confirmed dur-
ing oral argument, the statute authorizes procedures for
the reclassification of Schedule I drugs. But perhaps even
more important than these legal avenues is the democratic
——————
street”).
 Cite as: 545 U. S. ____ (2005) 31

Opinion of the Court

process, in which the voices of voters allied with these
respondents may one day be heard in the halls of Con-
gress. Under the present state of the law, however, the
judgment of the Court of Appeals must be vacated. The
case is remanded for further proceedings consistent with
this opinion.
It is so ordered.
 Cite as: 545 U. S. ____ (2005) 1

SCALIA, J., concurring in judgment

SUPREME COURT OF THE UNITED STATES
_________________

No. 03–1454
_________________

ALBERTO R. GONZALES, ATTORNEY GENERAL, ET
AL., PETITIONERS
v. ANGEL MCCLARY RAICH ET AL.
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE NINTH CIRCUIT
[June 6, 2005]

JUSTICE SCALIA, concurring in the judgment.
I agree with the Court’s holding that the Controlled
Substances Act (CSA) may validly be applied to respon-
dents’ cultivation, distribution, and possession of mari-
juana for personal, medicinal use. I write separately
because my understanding of the doctrinal foundation on
which that holding rests is, if not inconsistent with that of
the Court, at least more nuanced.
Since Perez v. United States, 402 U. S. 146 (1971), our
cases have mechanically recited that the Commerce
Clause permits congressional regulation of three catego-
ries: (1) the channels of interstate commerce; (2) the in-
strumentalities of interstate commerce, and persons or
things in interstate commerce; and (3) activities that
“substantially affect” interstate commerce. Id., at 150; see
United States v. Morrison, 529 U. S. 598, 608–609 (2000);
United States v. Lopez, 514 U. S. 549, 558–559 (1995); Hodel
v. Virginia Surface Mining & Reclamation Assn., Inc., 452
U. S. 264, 276–277 (1981). The first two categories are self-
evident, since they are the ingredients of interstate com-
merce itself. See Gibbons v. Ogden, 9 Wheat. 1, 189–190
(1824). The third category, however, is different in kind,
and its recitation without explanation is misleading and
incomplete.
It is misleading because, unlike the channels, instru-
2 GONZALES v. RAICH

SCALIA, J., concurring in judgment

mentalities, and agents of interstate commerce, activities
that substantially affect interstate commerce are not
themselves part of interstate commerce, and thus the
power to regulate them cannot come from the Commerce
Clause alone. Rather, as this Court has acknowledged
since at least United States v. Coombs, 12 Pet. 72 (1838),
Congress’s regulatory authority over intrastate activities
that are not themselves part of interstate commerce (in-
cluding activities that have a substantial effect on inter-
state commerce) derives from the Necessary and Proper
Clause. Id., at 78; Katzenbach v. McClung, 379 U. S. 294,
301–302 (1964); United States v. Wrightwood Dairy Co., 315
U. S. 110, 119 (1942); Shreveport Rate Cases, 234 U. S. 342,
353 (1914); United States v. E. C. Knight Co., 156 U. S. 1,
39–40 (1895) (Harlan, J., dissenting).1 And the category of
“activities that substantially affect interstate commerce,”
Lopez, supra, at 559, is incomplete because the authority to
enact laws necessary and proper for the regulation of
interstate commerce is not limited to laws governing
intrastate activities that substantially affect interstate
commerce. Where necessary to make a regulation of
interstate commerce effective, Congress may regulate even
those intrastate activities that do not themselves substan-
tially affect interstate commerce.
I
Our cases show that the regulation of intrastate activi-
ties may be necessary to and proper for the regulation of
interstate commerce in two general circumstances. Most
directly, the commerce power permits Congress not only to
devise rules for the governance of commerce between
——————
1 See also Garcia v. San Antonio Metropolitan Transit Authority, 469

U. S. 528, 584–585 (1985) (O’CONNOR, J., dissenting) (explaining that it is
through the Necessary and Proper Clause that “an intrastate activity
‘affecting’ interstate commerce can be reached through the commerce
power”).
 Cite as: 545 U. S. ____ (2005) 3

SCALIA, J., concurring in judgment

States but also to facilitate interstate commerce by elimi-
nating potential obstructions, and to restrict it by elimi-
nating potential stimulants. See NLRB v. Jones & Laugh-
lin Steel Corp., 301 U. S. 1, 36–37 (1937). That is why the
Court has repeatedly sustained congressional legislation
on the ground that the regulated activities had a substan-
tial effect on interstate commerce. See, e.g., Hodel, supra,
at 281 (surface coal mining); Katzenbach, supra, at 300
(discrimination by restaurants); Heart of Atlanta Motel, Inc.
v. United States, 379 U. S. 241, 258 (1964) (discrimination
by hotels); Mandeville Island Farms v. American Crystal
Sugar Co., 334 U. S. 219, 237 (1948) (intrastate price-
fixing); Board of Trade of Chicago v. Olsen, 262 U. S. 1, 40
(1923) (activities of a local grain exchange); Stafford v.
Wallace, 258 U. S. 495, 517, 524–525 (1922) (intrastate
transactions at stockyard). Lopez and Morrison recognized
the expansive scope of Congress’s authority in this regard:
“[T]he pattern is clear. Where economic activity substan-
tially affects interstate commerce, legislation regulating
that activity will be sustained.” Lopez, supra, at 560;
Morrison, supra, at 610 (same).
This principle is not without limitation. In Lopez and
Morrison, the Court—conscious of the potential of the
“substantially affects” test to “ ‘obliterate the distinction
between what is national and what is local,’ ” Lopez, supra,
at 566–567 (quoting A. L. A. Schechter Poultry Corp. v.
United States, 295 U. S. 495, 554 (1935)); see also Morrison,
supra, at 615–616—rejected the argument that Congress
may regulate noneconomic activity based solely on the
effect that it may have on interstate commerce through a
remote chain of inferences. Lopez, supra, at 564–566;
Morrison, supra, at 617–618. “[I]f we were to accept [such]
arguments,” the Court reasoned in Lopez, “we are hard
pressed to posit any activity by an individual that Con-
gress is without power to regulate.” Lopez, supra, at 564;
see also Morrison, supra, at 615–616. Thus, although
4 GONZALES v. RAICH

SCALIA, J., concurring in judgment

Congress’s authority to regulate intrastate activity that
substantially affects interstate commerce is broad, it does
not permit the Court to “pile inference upon inference,”
Lopez, supra, at 567, in order to establish that none-
conomic activity has a substantial effect on interstate
commerce.
As we implicitly acknowledged in Lopez, however, Con-
gress’s authority to enact laws necessary and proper for
the regulation of interstate commerce is not limited to
laws directed against economic activities that have a
substantial effect on interstate commerce. Though the
conduct in Lopez was not economic, the Court nevertheless
recognized that it could be regulated as “an essential part
of a larger regulation of economic activity, in which the
regulatory scheme could be undercut unless the intrastate
activity were regulated.” 514 U. S., at 561. This state-
ment referred to those cases permitting the regulation of
intrastate activities “which in a substantial way interfere
with or obstruct the exercise of the granted power.”
Wrightwood Dairy Co., 315 U. S., at 119; see also United
States v. Darby, 312 U. S. 100, 118–119 (1941); Shreveport
Rate Cases, 234 U. S., at 353. As the Court put it in
Wrightwood Dairy, where Congress has the authority to
enact a regulation of interstate commerce, “it possesses
every power needed to make that regulation effective.”
315 U. S., at 118–119.
Although this power “to make . . . regulation effective”
commonly overlaps with the authority to regulate eco-
nomic activities that substantially affect interstate com-
merce,2 and may in some cases have been confused with
——————
2 Wickard v. Filburn, 317 U. S. 111 (1942), presented such a case.

Because the unregulated production of wheat for personal consumption
diminished demand in the regulated wheat market, the Court said, it
carried with it the potential to disrupt Congress’s price regulation by
driving down prices in the market. Id., at 127–129. This potential
disruption of Congress’s interstate regulation, and not only the effect
 Cite as: 545 U. S. ____ (2005) 5

SCALIA, J., concurring in judgment

that authority, the two are distinct. The regulation of an
intrastate activity may be essential to a comprehensive
regulation of interstate commerce even though the intra-
state activity does not itself “substantially affect” inter-
state commerce. Moreover, as the passage from Lopez
quoted above suggests, Congress may regulate even none-
conomic local activity if that regulation is a necessary part
of a more general regulation of interstate commerce. See
Lopez, supra, at 561. The relevant question is simply
whether the means chosen are “reasonably adapted” to the
attainment of a legitimate end under the commerce power.
See Darby, supra, at 121.
In Darby, for instance, the Court explained that “Con-
gress, having . . . adopted the policy of excluding from
interstate commerce all goods produced for the commerce
which do not conform to the specified labor standards,”
312 U. S., at 121, could not only require employers en-
gaged in the production of goods for interstate commerce
to conform to wage and hour standards, id., at 119–121,
but could also require those employers to keep employ-
ment records in order to demonstrate compliance with the
regulatory scheme, id., at 125. While the Court sustained
the former regulation on the alternative ground that the
activity it regulated could have a “great effect” on inter-
state commerce, id., at 122–123, it affirmed the latter on
the sole ground that “[t]he requirement for records even of
the intrastate transaction is an appropriate means to a
legitimate end,” id., at 125.
As the Court said in the Shreveport Rate Cases, the
Necessary and Proper Clause does not give “Congress . . .
the authority to regulate the internal commerce of a State,
as such,” but it does allow Congress “to take all measures
necessary or appropriate to” the effective regulation of the
——————
that personal consumption of wheat had on interstate commerce,
justified Congress’s regulation of that conduct. Id., at 128–129.
6 GONZALES v. RAICH

SCALIA, J., concurring in judgment

interstate market, “although intrastate transactions . . .
may thereby be controlled.” 234 U. S., at 353; see also
Jones & Laughlin Steel Corp., 301 U. S., at 38 (the logic of
the Shreveport Rate Cases is not limited to instrumentali-
ties of commerce).
II
Today’s principal dissent objects that, by permitting
Congress to regulate activities necessary to effective inter-
state regulation, the Court reduces Lopez and Morrison to
“little more than a drafting guide.” Post, at 5 (opinion of
O’CONNOR, J.). I think that criticism unjustified. Unlike
the power to regulate activities that have a substantial
effect on interstate commerce, the power to enact laws
enabling effective regulation of interstate commerce can
only be exercised in conjunction with congressional regula-
tion of an interstate market, and it extends only to those
measures necessary to make the interstate regulation
effective. As Lopez itself states, and the Court affirms
today, Congress may regulate noneconomic intrastate
activities only where the failure to do so “could . . . under-
cut” its regulation of interstate commerce. See Lopez,
supra, at 561; ante, at 15, 21, 22. This is not a power that
threatens to obliterate the line between “what is truly
national and what is truly local.” Lopez, supra, at 567–
568.
Lopez and Morrison affirm that Congress may not regu-
late certain “purely local” activity within the States based
solely on the attenuated effect that such activity may have
in the interstate market. But those decisions do not de-
clare noneconomic intrastate activities to be categorically
beyond the reach of the Federal Government. Neither
case involved the power of Congress to exert control over
intrastate activities in connection with a more comprehen-
sive scheme of regulation; Lopez expressly disclaimed that
it was such a case, 514 U. S., at 561, and Morrison did not
 Cite as: 545 U. S. ____ (2005) 7

SCALIA, J., concurring in judgment

even discuss the possibility that it was. (The Court of
Appeals in Morrison made clear that it was not. See
Brzonkala v. Virginia Polytechnic Inst., 169 F. 3d 820,
834–835 (CA4 1999) (en banc).) To dismiss this distinction
as “superficial and formalistic,” see post, at 6 (O’CONNOR,
J., dissenting), is to misunderstand the nature of the
Necessary and Proper Clause, which empowers Congress
to enact laws in effectuation of its enumerated powers that
are not within its authority to enact in isolation. See
McCulloch v. Maryland, 4 Wheat. 316, 421–422 (1819).
And there are other restraints upon the Necessary and
Proper Clause authority. As Chief Justice Marshall wrote
in McCulloch v. Maryland, even when the end is constitu-
tional and legitimate, the means must be “appropriate”
and “plainly adapted” to that end. Id., at 421. Moreover,
they may not be otherwise “prohibited” and must be “con-
sistent with the letter and spirit of the constitution.” Ibid.
These phrases are not merely hortatory. For example,
cases such as Printz v. United States, 521 U. S. 898 (1997),
and New York v. United States, 505 U. S. 144 (1992),
affirm that a law is not “ ‘proper for carrying into Execu-
tion the Commerce Clause’ ” “[w]hen [it] violates [a consti-
tutional] principle of state sovereignty.” Printz, supra, at
923–924; see also New York, supra, at 166.
III
The application of these principles to the case before us
is straightforward. In the CSA, Congress has undertaken
to extinguish the interstate market in Schedule I con-
trolled substances, including marijuana. The Commerce
Clause unquestionably permits this. The power to regu-
late interstate commerce “extends not only to those regu-
lations which aid, foster and protect the commerce, but
embraces those which prohibit it.” Darby, 312 U. S., at
113. See also Hipolite Egg Co. v. United States, 220 U. S.
45, 58 (1911); Lottery Case, 188 U. S. 321, 354 (1903). To
8 GONZALES v. RAICH

SCALIA, J., concurring in judgment

effectuate its objective, Congress has prohibited almost all
intrastate activities related to Schedule I substances—
both economic activities (manufacture, distribution, pos-
session with the intent to distribute) and noneconomic
activities (simple possession). See 21 U. S. C. §§841(a),
844(a). That simple possession is a noneconomic activity
is immaterial to whether it can be prohibited as a neces-
sary part of a larger regulation. Rather, Congress’s au-
thority to enact all of these prohibitions of intrastate
controlled-substance activities depends only upon whether
they are appropriate means of achieving the legitimate
end of eradicating Schedule I substances from interstate
commerce.
By this measure, I think the regulation must be sus-
tained. Not only is it impossible to distinguish “controlled
substances manufactured and distributed intrastate” from
“controlled substances manufactured and distributed
interstate,” but it hardly makes sense to speak in such
terms. Drugs like marijuana are fungible commodities.
As the Court explains, marijuana that is grown at home
and possessed for personal use is never more than an
instant from the interstate market—and this is so
whether or not the possession is for medicinal use or law-
ful use under the laws of a particular State.3 See ante, at
——————
3 The principal dissent claims that, if this is sufficient to sustain the

regulation at issue in this case, then it should also have been sufficient
to sustain the regulation at issue in United States v. Lopez, 514 U. S.
549 (1995). See post, at 11–12 (arguing that “we could have surmised
in Lopez that guns in school zones are ‘never more than an instant from
the interstate market’ in guns already subject to federal regulation,
recast Lopez as a Necessary and Proper Clause case, and thereby
upheld the Gun-Free School Zones Act”). This claim founders upon the
shoals of Lopez itself, which made clear that the statute there at issue
was “not an essential part of a larger regulation of economic activity.”
Lopez, supra, at 561 (emphasis added). On the dissent’s view of things,
that statement is inexplicable. Of course it is in addition difficult to
imagine what intelligible scheme of regulation of the interstate market
 Cite as: 545 U. S. ____ (2005) 9

SCALIA, J., concurring in judgment

23–30. Congress need not accept on faith that state law
will be effective in maintaining a strict division between a
lawful market for “medical” marijuana and the more
general marijuana market. See id., at 26–27, and n. 38.
“To impose on [Congress] the necessity of resorting to
means which it cannot control, which another government
may furnish or withhold, would render its course precari-
ous, the result of its measures uncertain, and create a
dependence on other governments, which might disap-
point its most important designs, and is incompatible with
the language of the constitution.” McCulloch, supra, at
424.
Finally, neither respondents nor the dissenters suggest
any violation of state sovereignty of the sort that would
render this regulation “inappropriate,” id., at 421—except
to argue that the CSA regulates an area typically left to
state regulation. See post, at 6–7, 11 (opinion of
O’CONNOR, J.); post, at 8–9 (opinion of THOMAS, J.); Brief
for Respondents 39–42. That is not enough to render
federal regulation an inappropriate means. The Court has
repeatedly recognized that, if authorized by the commerce
power, Congress may regulate private endeavors “even
when [that regulation] may pre-empt express state-law
determinations contrary to the result which has com-
mended itself to the collective wisdom of Congress.” Na-
tional League of Cities v. Usery, 426 U. S. 833, 840 (1976);
see Cleveland v. United States, 329 U. S. 14, 19 (1946);

——————
in guns could have as an appropriate means of effectuation the prohibi-
tion of guns within 1000 feet of schools (and nowhere else). The dissent
points to a federal law, 18 U. S. C. §922(b)(1), barring licensed dealers
from selling guns to minors, see post, at 12, but the relationship be-
tween the regulatory scheme of which §922(b)(1) is a part (requiring all
dealers in firearms that have traveled in interstate commerce to be
licensed, see §922(a)) and the statute at issue in Lopez approaches the
nonexistent—which is doubtless why the Government did not attempt
to justify the statute on the basis of that relationship.
10 GONZALES v. RAICH

SCALIA, J., concurring in judgment

McCulloch, supra, at 424. At bottom, respondents’ state-
sovereignty argument reduces to the contention that
federal regulation of the activities permitted by Califor-
nia’s Compassionate Use Act is not sufficiently necessary
to be “necessary and proper” to Congress’s regulation of
the interstate market. For the reasons given above and in
the Court’s opinion, I cannot agree.
* * *
I thus agree with the Court that, however the class of
regulated activities is subdivided, Congress could rea-
sonably conclude that its objective of prohibiting mari-
juana from the interstate market “could be undercut” if
those activities were excepted from its general scheme of
regulation. See Lopez, 514 U. S., at 561. That is sufficient
to authorize the application of the CSA to respondents.
 Cite as: 545 U. S. ____ (2005) 1

O’CONNOR, J., dissenting

SUPREME COURT OF THE UNITED STATES
_________________

No. 03–1454
_________________

ALBERTO R. GONZALES, ATTORNEY GENERAL, ET
AL., PETITIONERS
v. ANGEL MCCLARY RAICH ET AL.
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE NINTH CIRCUIT
[June 6, 2005]

JUSTICE O’CONNOR, with whom THE CHIEF JUSTICE and
JUSTICE THOMAS join as to all but Part III, dissenting.
We enforce the “outer limits” of Congress’ Commerce
Clause authority not for their own sake, but to protect
historic spheres of state sovereignty from excessive federal
encroachment and thereby to maintain the distribution of
power fundamental to our federalist system of govern-
ment. United States v. Lopez, 514 U. S. 549, 557 (1995);
NLRB v. Jones & Laughlin Steel Corp., 301 U. S. 1, 37
(1937). One of federalism’s chief virtues, of course, is that
it promotes innovation by allowing for the possibility that
“a single courageous State may, if its citizens choose, serve
as a laboratory; and try novel social and economic experi-
ments without risk to the rest of the country.” New State
Ice Co. v. Liebmann, 285 U. S. 262, 311 (1932) (Brandeis,
J., dissenting).
This case exemplifies the role of States as laboratories.
The States’ core police powers have always included au-
thority to define criminal law and to protect the health,
safety, and welfare of their citizens. Brecht v. Abraham-
son, 507 U. S. 619, 635 (1993); Whalen v. Roe, 429 U. S.
589, 603, n. 30 (1977). Exercising those powers, California
(by ballot initiative and then by legislative codification)
has come to its own conclusion about the difficult and
sensitive question of whether marijuana should be avail-
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O’CONNOR, J., dissenting

able to relieve severe pain and suffering. Today the Court
sanctions an application of the federal Controlled Sub-
stances Act that extinguishes that experiment, without
any proof that the personal cultivation, possession, and
use of marijuana for medicinal purposes, if economic
activity in the first place, has a substantial effect on inter-
state commerce and is therefore an appropriate subject of
federal regulation. In so doing, the Court announces a
rule that gives Congress a perverse incentive to legislate
broadly pursuant to the Commerce Clause—nestling
questionable assertions of its authority into comprehen-
sive regulatory schemes—rather than with precision.
That rule and the result it produces in this case are irrec-
oncilable with our decisions in Lopez, supra, and United
States v. Morrison, 529 U. S. 598 (2000). Accordingly I
dissent.
I
In Lopez, we considered the constitutionality of the Gun-
Free School Zones Act of 1990, which made it a federal
offense “for any individual knowingly to possess a firearm
. . . at a place the individual knows, or has reasonable
cause to believe, is a school zone,” 18 U. S. C.
§922(q)(2)(A). We explained that “Congress’ commerce
authority includes the power to regulate those activities
having a substantial relation to interstate commerce . . . ,
i.e., those activities that substantially affect interstate
commerce.” 514 U. S., at 558–559 (citation omitted). This
power derives from the conjunction of the Commerce
Clause and the Necessary and Proper Clause. Garcia v.
San Antonio Metropolitan Transit Authority, 469 U. S.
528, 585–586 (1985) (O’CONNOR, J., dissenting) (explain-
ing that United States v. Darby, 312 U. S. 100 (1941),
United States v. Wrightwood Dairy Co., 315 U. S. 110
(1942), and Wickard v. Filburn, 317 U. S. 111 (1942),
based their expansion of the commerce power on the Nec-
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O’CONNOR, J., dissenting

essary and Proper Clause, and that “the reasoning of these
cases underlies every recent decision concerning the reach
of Congress to activities affecting interstate commerce”);
ante, at 2 (SCALIA, J., concurring in judgment). We held in
Lopez that the Gun-Free School Zones Act could not be
sustained as an exercise of that power.
Our decision about whether gun possession in school
zones substantially affected interstate commerce turned
on four considerations. Lopez, supra, at 559–567; see also
Morrison, supra, at 609–613. First, we observed that our
“substantial effects” cases generally have upheld federal
regulation of economic activity that affected interstate
commerce, but that §922(q) was a criminal statute having
“nothing to do with ‘commerce’ or any sort of economic
enterprise.” Lopez, 514 U. S., at 561. In this regard, we
also noted that “[s]ection 922(q) is not an essential part of
a larger regulation of economic activity, in which the
regulatory scheme could be undercut unless the intrastate
activity were regulated. It cannot, therefore, be sustained
under our cases upholding regulations of activities that
arise out of or are connected with a commercial transac-
tion, which viewed in the aggregate, substantially affects
interstate commerce.” Ibid. Second, we noted that the
statute contained no express jurisdictional requirement
establishing its connection to interstate commerce. Ibid.
Third, we found telling the absence of legislative find-
ings about the regulated conduct’s impact on interstate
commerce. We explained that while express legislative
findings are neither required nor, when provided, disposi-
tive, findings “enable us to evaluate the legislative judg-
ment that the activity in question substantially affect[s]
interstate commerce, even though no such substantial
effect [is] visible to the naked eye.” Id., at 563. Finally,
we rejected as too attenuated the Government’s argument
that firearm possession in school zones could result in
violent crime which in turn could adversely affect the
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O’CONNOR, J., dissenting

national economy. Id., at 563–567. The Constitution, we
said, does not tolerate reasoning that would “convert
congressional authority under the Commerce Clause to a
general police power of the sort retained by the States.”
Id., at 567. Later in Morrison, supra, we relied on the
same four considerations to hold that §40302 of the Vio-
lence Against Women Act of 1994, 42 U. S. C. §13981,
exceeded Congress’ authority under the Commerce Clause.
In my view, the case before us is materially indistin-
guishable from Lopez and Morrison when the same con-
siderations are taken into account.
II
A
What is the relevant conduct subject to Commerce
Clause analysis in this case? The Court takes its cues
from Congress, applying the above considerations to the
activity regulated by the Controlled Substances Act (CSA)
in general. The Court’s decision rests on two facts about
the CSA: (1) Congress chose to enact a single statute
providing a comprehensive prohibition on the production,
distribution, and possession of all controlled substances,
and (2) Congress did not distinguish between various
forms of intrastate noncommercial cultivation, possession,
and use of marijuana. See 21 U. S. C. §§841(a)(1), 844(a).
Today’s decision suggests that the federal regulation of
local activity is immune to Commerce Clause challenge
because Congress chose to act with an ambitious, all-
encompassing statute, rather than piecemeal. In my view,
allowing Congress to set the terms of the constitutional
debate in this way, i.e., by packaging regulation of local
activity in broader schemes, is tantamount to removing
meaningful limits on the Commerce Clause.
The Court’s principal means of distinguishing Lopez
from this case is to observe that the Gun-Free School
Zones Act of 1990 was a “brief, single-subject statute,”
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O’CONNOR, J., dissenting

ante, at 20, see also ante, at 19, whereas the CSA is “a
lengthy and detailed statute creating a comprehensive
framework for regulating the production, distribution, and
possession of five classes of ‘controlled substances,’ ” ibid.
Thus, according to the Court, it was possible in Lopez to
evaluate in isolation the constitutionality of criminalizing
local activity (there gun possession in school zones),
whereas the local activity that the CSA targets (in this
case cultivation and possession of marijuana for personal
medicinal use) cannot be separated from the general drug
control scheme of which it is a part.
Today’s decision allows Congress to regulate intrastate
activity without check, so long as there is some implication
by legislative design that regulating intrastate activity is
essential (and the Court appears to equate “essential” with
“necessary”) to the interstate regulatory scheme. Seizing
upon our language in Lopez that the statute prohibiting
gun possession in school zones was “not an essential part
of a larger regulation of economic activity, in which the
regulatory scheme could be undercut unless the intrastate
activity were regulated,” 514 U. S., at 561, the Court
appears to reason that the placement of local activity in a
comprehensive scheme confirms that it is essential to that
scheme. Ante, at 21–22. If the Court is right, then Lopez
stands for nothing more than a drafting guide: Congress
should have described the relevant crime as “transfer or
possession of a firearm anywhere in the nation”—thus
including commercial and noncommercial activity, and
clearly encompassing some activity with assuredly sub-
stantial effect on interstate commerce. Had it done so, the
majority hints, we would have sustained its authority to
regulate possession of firearms in school zones. Further-
more, today’s decision suggests we would readily sustain a
congressional decision to attach the regulation of intra-
state activity to a pre-existing comprehensive (or even not-
so-comprehensive) scheme. If so, the Court invites in-
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O’CONNOR, J., dissenting

creased federal regulation of local activity even if, as it
suggests, Congress would not enact a new interstate
scheme exclusively for the sake of reaching intrastate
activity, see ante, at 22, n. 33; ante, at 6 (SCALIA, J., con-
curring in judgment).
I cannot agree that our decision in Lopez contemplated
such evasive or overbroad legislative strategies with ap-
proval. Until today, such arguments have been made only
in dissent. See Morrison, 529 U. S., at 657 (BREYER, J.,
dissenting) (given that Congress can regulate “ ‘an essen-
tial part of a larger regulation of economic activity,’ ” “can
Congress save the present law by including it, or much of
it, in a broader ‘Safe Transport’ or ‘Worker Safety’ act?”).
Lopez and Morrison did not indicate that the constitution-
ality of federal regulation depends on superficial and
formalistic distinctions. Likewise I did not understand
our discussion of the role of courts in enforcing outer limits
of the Commerce Clause for the sake of maintaining the
federalist balance our Constitution requires, see Lopez,
514 U. S., at 557; id., at 578 (KENNEDY, J., concurring), as
a signal to Congress to enact legislation that is more
extensive and more intrusive into the domain of state
power. If the Court always defers to Congress as it does
today, little may be left to the notion of enumerated
powers.
The hard work for courts, then, is to identify objective
markers for confining the analysis in Commerce Clause
cases. Here, respondents challenge the constitutionality of
the CSA as applied to them and those similarly situated. I
agree with the Court that we must look beyond respon-
dents’ own activities. Otherwise, individual litigants could
always exempt themselves from Commerce Clause regula-
tion merely by pointing to the obvious—that their personal
activities do not have a substantial effect on interstate
commerce. See Maryland v. Wirtz, 392 U. S. 183, 193
(1968); Wickard, 317 U. S., at 127–128. The task is to
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O’CONNOR, J., dissenting

identify a mode of analysis that allows Congress to regu-
late more than nothing (by declining to reduce each case to
its litigants) and less than everything (by declining to let
Congress set the terms of analysis). The analysis may not
be the same in every case, for it depends on the regulatory
scheme at issue and the federalism concerns implicated.
See generally Lopez, 514 U. S., at 567; id., at 579
(KENNEDY, J., concurring).
A number of objective markers are available to confine
the scope of constitutional review here. Both federal and
state legislation—including the CSA itself, the California
Compassionate Use Act, and other state medical mari-
juana legislation—recognize that medical and nonmedical
(i.e., recreational) uses of drugs are realistically distinct
and can be segregated, and regulate them differently. See
21 U. S. C. §812; Cal. Health & Safety Code Ann. §11362.5
(West Supp. 2005); ante, at 1 (opinion of the Court). Re-
spondents challenge only the application of the CSA to
medicinal use of marijuana. Cf. United States v. Raines,
362 U. S. 17, 20–22 (1960) (describing our preference for
as-applied rather than facial challenges). Moreover, be-
cause fundamental structural concerns about dual sover-
eignty animate our Commerce Clause cases, it is relevant
that this case involves the interplay of federal and state
regulation in areas of criminal law and social policy, where
“States lay claim by right of history and expertise.” Lopez,
supra, at 583 (KENNEDY, J., concurring); see also Morri-
son, supra, at 617–619; Lopez, supra, at 580 (KENNEDY, J.,
concurring) (“The statute before us upsets the federal
balance to a degree that renders it an unconstitutional
assertion of the commerce power, and our intervention is
required”); cf. Garcia, 469 U. S., at 586 (O’CONNOR, J.,
dissenting) (“[S]tate autonomy is a relevant factor in
assessing the means by which Congress exercises its
powers” under the Commerce Clause). California, like
other States, has drawn on its reserved powers to distin-
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O’CONNOR, J., dissenting

guish the regulation of medicinal marijuana. To ascertain
whether Congress’ encroachment is constitutionally justi-
fied in this case, then, I would focus here on the personal
cultivation, possession, and use of marijuana for medicinal
purposes.
B
Having thus defined the relevant conduct, we must
determine whether, under our precedents, the conduct is
economic and, in the aggregate, substantially affects
interstate commerce. Even if intrastate cultivation and
possession of marijuana for one’s own medicinal use can
properly be characterized as economic, and I question
whether it can, it has not been shown that such activity
substantially affects interstate commerce. Similarly, it is
neither self-evident nor demonstrated that regulating
such activity is necessary to the interstate drug control
scheme.
The Court’s definition of economic activity is breathtak-
ing. It defines as economic any activity involving the
production, distribution, and consumption of commodities.
And it appears to reason that when an interstate market
for a commodity exists, regulating the intrastate manufac-
ture or possession of that commodity is constitutional
either because that intrastate activity is itself economic, or
because regulating it is a rational part of regulating its
market. Putting to one side the problem endemic to the
Court’s opinion—the shift in focus from the activity at
issue in this case to the entirety of what the CSA regu-
lates, see Lopez, supra, at 565 (“depending on the level of
generality, any activity can be looked upon as commer-
cial”)—the Court’s definition of economic activity for pur-
poses of Commerce Clause jurisprudence threatens to
sweep all of productive human activity into federal regula-
tory reach.
The Court uses a dictionary definition of economics to
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O’CONNOR, J., dissenting

skirt the real problem of drawing a meaningful line be-
tween “what is national and what is local,” Jones &
Laughlin Steel, 301 U. S., at 37. It will not do to say that
Congress may regulate noncommercial activity simply
because it may have an effect on the demand for commer-
cial goods, or because the noncommercial endeavor can, in
some sense, substitute for commercial activity. Most
commercial goods or services have some sort of privately
producible analogue. Home care substitutes for daycare.
Charades games substitute for movie tickets. Backyard or
windowsill gardening substitutes for going to the super-
market. To draw the line wherever private activity affects
the demand for market goods is to draw no line at all, and
to declare everything economic. We have already rejected
the result that would follow—a federal police power.
Lopez, supra, at 564.
In Lopez and Morrison, we suggested that economic
activity usually relates directly to commercial activity.
See Morrison, 529 U. S., at 611, n. 4 (intrastate activities
that have been within Congress’ power to regulate have
been “of an apparent commercial character”); Lopez, 514
U. S., at 561 (distinguishing the Gun-Free School Zones
Act of 1990 from “activities that arise out of or are con-
nected with a commercial transaction”). The homegrown
cultivation and personal possession and use of marijuana
for medicinal purposes has no apparent commercial char-
acter. Everyone agrees that the marijuana at issue in this
case was never in the stream of commerce, and neither
were the supplies for growing it. (Marijuana is highly
unusual among the substances subject to the CSA in that
it can be cultivated without any materials that have trav-
eled in interstate commerce.) Lopez makes clear that
possession is not itself commercial activity. Ibid. And
respondents have not come into possession by means of
any commercial transaction; they have simply grown, in
their own homes, marijuana for their own use, without
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O’CONNOR, J., dissenting

acquiring, buying, selling, or bartering a thing of value.
Cf. id., at 583 (KENNEDY, J., concurring) (“The statute now
before us forecloses the States from experimenting . . . and
it does so by regulating an activity beyond the realm of
commerce in the ordinary and usual sense of that term”).
The Court suggests that Wickard, which we have identi-
fied as “perhaps the most far reaching example of Com-
merce Clause authority over intrastate activity,” Lopez,
supra, at 560, established federal regulatory power over
any home consumption of a commodity for which a na-
tional market exists. I disagree. Wickard involved a
challenge to the Agricultural Adjustment Act of 1938
(AAA), which directed the Secretary of Agriculture to set
national quotas on wheat production, and penalties for
excess production. 317 U. S., at 115–116. The AAA itself
confirmed that Congress made an explicit choice not to
reach—and thus the Court could not possibly have ap-
proved of federal control over—small-scale, noncommercial
wheat farming. In contrast to the CSA’s limitless asser-
tion of power, Congress provided an exemption within the
AAA for small producers. When Filburn planted the
wheat at issue in Wickard, the statute exempted plantings
less than 200 bushels (about six tons), and when he har-
vested his wheat it exempted plantings less than six acres.
Id., at 130, n. 30. Wickard, then, did not extend Com-
merce Clause authority to something as modest as the
home cook’s herb garden. This is not to say that Congress
may never regulate small quantities of commodities pos-
sessed or produced for personal use, or to deny that it
sometimes needs to enact a zero tolerance regime for such
commodities. It is merely to say that Wickard did not hold
or imply that small-scale production of commodities is
always economic, and automatically within Congress’
reach.
Even assuming that economic activity is at issue in this
case, the Government has made no showing in fact that
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O’CONNOR, J., dissenting

the possession and use of homegrown marijuana for medi-
cal purposes, in California or elsewhere, has a substantial
effect on interstate commerce. Similarly, the Government
has not shown that regulating such activity is necessary to
an interstate regulatory scheme. Whatever the specific
theory of “substantial effects” at issue (i.e., whether the
activity substantially affects interstate commerce,
whether its regulation is necessary to an interstate regu-
latory scheme, or both), a concern for dual sovereignty
requires that Congress’ excursion into the traditional
domain of States be justified.
That is why characterizing this as a case about the
Necessary and Proper Clause does not change the analysis
significantly. Congress must exercise its authority under
the Necessary and Proper Clause in a manner consistent
with basic constitutional principles. Garcia, 469 U. S., at
585 (O’CONNOR, J., dissenting) (“It is not enough that the
‘end be legitimate’; the means to that end chosen by Con-
gress must not contravene the spirit of the Constitution”).
As JUSTICE SCALIA recognizes, see ante, at 7 (opinion
concurring in judgment), Congress cannot use its author-
ity under the Clause to contravene the principle of state
sovereignty embodied in the Tenth Amendment. Ibid.
Likewise, that authority must be used in a manner consis-
tent with the notion of enumerated powers—a structural
principle that is as much part of the Constitution as the
Tenth Amendment’s explicit textual command. Accord-
ingly, something more than mere assertion is required
when Congress purports to have power over local activity
whose connection to an intrastate market is not self-
evident. Otherwise, the Necessary and Proper Clause will
always be a back door for unconstitutional federal regula-
tion. Cf. Printz v. United States, 521 U. S. 898, 923 (1997)
(the Necessary and Proper Clause is “the last, best hope of
those who defend ultra vires congressional action”). In-
deed, if it were enough in “substantial effects” cases for
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O’CONNOR, J., dissenting

the Court to supply conceivable justifications for intra-
state regulation related to an interstate market, then we
could have surmised in Lopez that guns in school zones
are “never more than an instant from the interstate mar-
ket” in guns already subject to extensive federal regula-
tion, ante, at 8 (SCALIA, J., concurring in judgment), recast
Lopez as a Necessary and Proper Clause case, and thereby
upheld the Gun-Free School Zones Act of 1990. (According
to the Court’s and the concurrence’s logic, for example, the
Lopez court should have reasoned that the prohibition on
gun possession in school zones could be an appropriate
means of effectuating a related prohibition on “sell[ing]” or
“deliver[ing]” firearms or ammunition to “any individual
who the licensee knows or has reasonable cause to believe
is less than eighteen years of age.” 18 U. S. C. §922(b)(1)
(1988 ed., Supp. II).)
There is simply no evidence that homegrown medicinal
marijuana users constitute, in the aggregate, a sizable
enough class to have a discernable, let alone substantial,
impact on the national illicit drug market—or otherwise to
threaten the CSA regime. Explicit evidence is helpful
when substantial effect is not “visible to the naked eye.”
See Lopez, 514 U. S., at 563. And here, in part because
common sense suggests that medical marijuana users may
be limited in number and that California’s Compassionate
Use Act and similar state legislation may well isolate
activities relating to medicinal marijuana from the illicit
market, the effect of those activities on interstate drug
traffic is not self-evidently substantial.
In this regard, again, this case is readily distinguishable
from Wickard. To decide whether the Secretary could
regulate local wheat farming, the Court looked to “the
actual effects of the activity in question upon interstate
commerce.” 317 U. S., at 120. Critically, the Court was
able to consider “actual effects” because the parties had
“stipulated a summary of the economics of the wheat
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O’CONNOR, J., dissenting

industry.” Id., at 125. After reviewing in detail the pic-
ture of the industry provided in that summary, the Court
explained that consumption of homegrown wheat was the
most variable factor in the size of the national wheat crop,
and that on-site consumption could have the effect of
varying the amount of wheat sent to market by as much as
20 percent. Id., at 127. With real numbers at hand, the
Wickard Court could easily conclude that “a factor of such
volume and variability as home-consumed wheat would
have a substantial influence on price and market condi-
tions” nationwide. Id., at 128; see also id., at 128–129
(“This record leaves us in no doubt” about substantial
effects).
The Court recognizes that “the record in the Wickard
case itself established the causal connection between the
production for local use and the national market” and
argues that “we have before us findings by Congress to the
same effect.” Ante, at 17 (emphasis added). The Court
refers to a series of declarations in the introduction to the
CSA saying that (1) local distribution and possession of
controlled substances causes “swelling” in interstate traf-
fic; (2) local production and distribution cannot be distin-
guished from interstate production and distribution; (3)
federal control over intrastate incidents “is essential to
effective control” over interstate drug trafficking. 21
U. S. C. §§801(1)–(6). These bare declarations cannot be
compared to the record before the Court in Wickard.
They amount to nothing more than a legislative insis-
tence that the regulation of controlled substances must be
absolute. They are asserted without any supporting evi-
dence—descriptive, statistical, or otherwise. “[S]imply
because Congress may conclude a particular activity sub-
stantially affects interstate commerce does not necessarily
make it so.” Hodel v. Virginia Surface Mining & Reclama-
tion Assn., Inc., 452 U. S. 264, 311 (1981) (REHNQUIST, J.,
concurring in judgment). Indeed, if declarations like these
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O’CONNOR, J., dissenting

suffice to justify federal regulation, and if the Court today
is right about what passes rationality review before us,
then our decision in Morrison should have come out the
other way. In that case, Congress had supplied numerous
findings regarding the impact gender-motivated violence
had on the national economy. 529 U. S., at 614; id., at
628–636 (SOUTER, J., dissenting) (chronicling findings).
But, recognizing that “ ‘ “[w]hether particular operations
affect interstate commerce sufficiently to come under the
constitutional power of Congress to regulate them is ulti-
mately a judicial rather than a legislative question,” ’ ” we
found Congress’ detailed findings inadequate. Id., at 614
(quoting Lopez, supra, at 557, n. 2, in turn quoting Heart
of Atlanta Motel, Inc. v. United States, 379 U. S. 241, 273
(1964) (Black, J., concurring)). If, as the Court claims,
today’s decision does not break with precedent, how can it
be that voluminous findings, documenting extensive hear-
ings about the specific topic of violence against women, did
not pass constitutional muster in Morrison, while the
CSA’s abstract, unsubstantiated, generalized findings
about controlled substances do?
In particular, the CSA’s introductory declarations are
too vague and unspecific to demonstrate that the federal
statutory scheme will be undermined if Congress cannot
exert power over individuals like respondents. The decla-
rations are not even specific to marijuana. (Facts about
substantial effects may be developed in litigation to com-
pensate for the inadequacy of Congress’ findings; in part
because this case comes to us from the grant of a prelimi-
nary injunction, there has been no such development.)
Because here California, like other States, has carved out
a limited class of activity for distinct regulation, the in-
adequacy of the CSA’s findings is especially glaring. The
California Compassionate Use Act exempts from other
state drug laws patients and their caregivers “who pos-
ses[s] or cultivat[e] marijuana for the personal medical
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O’CONNOR, J., dissenting

purposes of the patient upon the written or oral recom-
mendation of a physician” to treat a list of serious medical
conditions. Cal. Health & Safety Code Ann. §§11362.5(d),
11362.7(h) (West Supp. 2005) (emphasis added). Compare
ibid. with, e.g., §11357(b) (West 1991) (criminalizing mari-
juana possession in excess of 28.5 grams); §11358 (crimi-
nalizing marijuana cultivation). The Act specifies that it
should not be construed to supersede legislation prohibit-
ing persons from engaging in acts dangerous to others, or
to condone the diversion of marijuana for nonmedical
purposes. §11362.5(b)(2) (West Supp. 2005). To promote
the Act’s operation and to facilitate law enforcement,
California recently enacted an identification card system
for qualified patients. §§11362.7–11362.83. We generally
assume States enforce their laws, see Riley v. National
Federation of Blind of N. C., Inc., 487 U. S. 781, 795
(1988), and have no reason to think otherwise here.
The Government has not overcome empirical doubt that
the number of Californians engaged in personal cultiva-
tion, possession, and use of medical marijuana, or the
amount of marijuana they produce, is enough to threaten
the federal regime. Nor has it shown that Compassionate
Use Act marijuana users have been or are realistically
likely to be responsible for the drug’s seeping into the
market in a significant way. The Government does cite
one estimate that there were over 100,000 Compassionate
Use Act users in California in 2004, Reply Brief for Peti-
tioners 16, but does not explain, in terms of proportions,
what their presence means for the national illicit drug
market. See generally Wirtz, 392 U. S., at 196, n. 27
(Congress cannot use “a relatively trivial impact on com-
merce as an excuse for broad general regulation of state or
private activities”); cf. General Accounting Office, Mari-
juana: Early Experience with Four States’ Laws That
Allow Use for Medical Purposes 21–23 (Rep. No. 03–189,
Nov. 2002), http://www.gao.gov/new.items/d03189.pdf (as
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O’CONNOR, J., dissenting

visited June 3, 2005 and available in Clerk of Court’s case
file) (in four California counties before the identification
card system was enacted, voluntarily registered medical
marijuana patients were less than 0.5 percent of the popu-
lation; in Alaska, Hawaii, and Oregon, statewide medical
marijuana registrants represented less than 0.05 percent
of the States’ populations). It also provides anecdotal
evidence about the CSA’s enforcement. See Reply Brief for
Petitioners 17–18. The Court also offers some arguments
about the effect of the Compassionate Use Act on the
national market. It says that the California statute might
be vulnerable to exploitation by unscrupulous physicians,
that Compassionate Use Act patients may overproduce,
and that the history of the narcotics trade shows the diffi-
culty of cordoning off any drug use from the rest of the
market. These arguments are plausible; if borne out in
fact they could justify prosecuting Compassionate Use Act
patients under the federal CSA. But, without substantia-
tion, they add little to the CSA’s conclusory statements
about diversion, essentiality, and market effect. Piling
assertion upon assertion does not, in my view, satisfy the
substantiality test of Lopez and Morrison.
III
We would do well to recall how James Madison, the
father of the Constitution, described our system of joint
sovereignty to the people of New York: “The powers dele-
gated by the proposed constitution to the federal govern-
ment are few and defined. Those which are to remain in
the State governments are numerous and indefinite. . . .
The powers reserved to the several States will extend to
all the objects which, in the ordinary course of affairs,
concern the lives, liberties, and properties of the people,
and the internal order, improvement, and prosperity of the
State.” The Federalist No. 45, pp. 292–293 (C. Rossiter ed.
1961).
 Cite as: 545 U. S. ____ (2005) 17

O’CONNOR, J., dissenting

Relying on Congress’ abstract assertions, the Court has
endorsed making it a federal crime to grow small amounts
of marijuana in one’s own home for one’s own medicinal
use. This overreaching stifles an express choice by some
States, concerned for the lives and liberties of their people,
to regulate medical marijuana differently. If I were a
California citizen, I would not have voted for the medical
marijuana ballot initiative; if I were a California legislator
I would not have supported the Compassionate Use Act.
But whatever the wisdom of California’s experiment with
medical marijuana, the federalism principles that have
driven our Commerce Clause cases require that room for
experiment be protected in this case. For these reasons I
dissent.
 Cite as: 545 U. S. ____ (2005) 1

THOMAS, J., dissenting

SUPREME COURT OF THE UNITED STATES
_________________

No. 03–1454
_________________

ALBERTO R. GONZALES, ATTORNEY GENERAL, ET
AL., PETITIONERS
v. ANGEL MCCLARY RAICH ET AL.
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE NINTH CIRCUIT
[June 6, 2005]

JUSTICE THOMAS, dissenting.
Respondents Diane Monson and Angel Raich use mari-
juana that has never been bought or sold, that has never
crossed state lines, and that has had no demonstrable
effect on the national market for marijuana. If Congress
can regulate this under the Commerce Clause, then it can
regulate virtually anything—and the Federal Government
is no longer one of limited and enumerated powers.
I
Respondents’ local cultivation and consumption of mari-
juana is not “Commerce . . . among the several States.”
U. S. Const., Art. I, §8, cl. 3. By holding that Congress
may regulate activity that is neither interstate nor com-
merce under the Interstate Commerce Clause, the Court
abandons any attempt to enforce the Constitution’s limits
on federal power. The majority supports this conclusion
by invoking, without explanation, the Necessary and
Proper Clause. Regulating respondents’ conduct, however,
is not “necessary and proper for carrying into Execution”
Congress’ restrictions on the interstate drug trade. Art. I,
§8, cl. 18. Thus, neither the Commerce Clause nor the
Necessary and Proper Clause grants Congress the power
to regulate respondents’ conduct.
2 GONZALES v. RAICH

THOMAS, J., dissenting

A
As I explained at length in United States v. Lopez, 514
U. S. 549 (1995), the Commerce Clause empowers Con-
gress to regulate the buying and selling of goods and
services trafficked across state lines. Id., at 586–589
(concurring opinion). The Clause’s text, structure, and
history all indicate that, at the time of the founding, the
term “ ‘commerce’ consisted of selling, buying, and barter-
ing, as well as transporting for these purposes.” Id., at
585 (THOMAS, J., concurring). Commerce, or trade, stood
in contrast to productive activities like manufacturing and
agriculture. Id., at 586–587 (THOMAS, J., concurring).
Throughout founding-era dictionaries, Madison’s notes
from the Constitutional Convention, The Federalist Pa-
pers, and the ratification debates, the term “commerce” is
consistently used to mean trade or exchange—not all
economic or gainful activity that has some attenuated
connection to trade or exchange. Ibid. (THOMAS, J., con-
curring); Barnett, The Original Meaning of the Commerce
Clause, 68 U. Chi. L. Rev. 101, 112–125 (2001). The term
“commerce” commonly meant trade or exchange (and
shipping for these purposes) not simply to those involved
in the drafting and ratification processes, but also to the
general public. Barnett, New Evidence of the Original
Meaning of the Commerce Clause, 55 Ark. L. Rev. 847,
857–862 (2003).
Even the majority does not argue that respondents’ con-
duct is itself “Commerce among the several States.” Art. I,
§8, cl. 3. Ante, at 19. Monson and Raich neither buy nor
sell the marijuana that they consume. They cultivate
their cannabis entirely in the State of California—it never
crosses state lines, much less as part of a commercial
transaction. Certainly no evidence from the founding
suggests that “commerce” included the mere possession of
a good or some purely personal activity that did not in-
volve trade or exchange for value. In the early days of the
 Cite as: 545 U. S. ____ (2005) 3

THOMAS, J., dissenting

Republic, it would have been unthinkable that Congress
could prohibit the local cultivation, possession, and con-
sumption of marijuana.
On this traditional understanding of “commerce,” the
Controlled Substances Act (CSA), 21 U. S. C. §801 et seq.,
regulates a great deal of marijuana trafficking that is
interstate and commercial in character. The CSA does
not, however, criminalize only the interstate buying and
selling of marijuana. Instead, it bans the entire market—
intrastate or interstate, noncommercial or commercial—
for marijuana. Respondents are correct that the CSA
exceeds Congress’ commerce power as applied to their
conduct, which is purely intrastate and noncommercial.
B
More difficult, however, is whether the CSA is a valid
exercise of Congress’ power to enact laws that are “neces-
sary and proper for carrying into Execution” its power to
regulate interstate commerce. Art. I, §8, cl. 18. The Neces-
sary and Proper Clause is not a warrant to Congress to
enact any law that bears some conceivable connection to the
exercise of an enumerated power.1 Nor is it, however, a
command to Congress to enact only laws that are absolutely
indispensable to the exercise of an enumerated power.2
In McCulloch v. Maryland, 4 Wheat. 316 (1819), this
Court, speaking through Chief Justice Marshall, set forth
a test for determining when an Act of Congress is permis-
sible under the Necessary and Proper Clause:
——————
1 McCulloch v. Maryland, 4 Wheat. 316, 419–421 (1819); Madison, The

Bank Bill, House of Representatives (Feb. 2, 1791), in 3 The Founders’
Constitution 244 (P. Kurland & R. Lerner eds. 1987) (requiring “direct”
rather than “remote” means-end fit); Hamilton, Opinion on the Constitu-
tionality of the Bank (Feb. 23, 1791), in id., at 248, 250 (requiring “obvi-
ous” means-end fit, where the end was “clearly comprehended within any
of the specified powers” of Congress).
2 McCulloch, supra, at 413–415; D. Currie, The Constitution in the

Supreme Court: The First Hundred Years 1789–1888, p. 162 (1985).
4 GONZALES v. RAICH

THOMAS, J., dissenting

“Let the end be legitimate, let it be within the scope of
the constitution, and all means which are appropriate,
which are plainly adapted to that end, which are not
prohibited, but consist with the letter and spirit of the
constitution, are constitutional.” Id., at 421.
To act under the Necessary and Proper Clause, then,
Congress must select a means that is “appropriate” and
“plainly adapted” to executing an enumerated power; the
means cannot be otherwise “prohibited” by the Constitu-
tion; and the means cannot be inconsistent with “the letter
and spirit of the [C]onstitution.” Ibid.; D. Currie, The
Constitution in the Supreme Court: The First Hundred
Years 1789–1888, pp. 163–164 (1985). The CSA, as ap-
plied to respondents’ conduct, is not a valid exercise of
Congress’ power under the Necessary and Proper Clause.
1
Congress has exercised its power over interstate com-
merce to criminalize trafficking in marijuana across state
lines. The Government contends that banning Monson
and Raich’s intrastate drug activity is “necessary and
proper for carrying into Execution” its regulation of inter-
state drug trafficking. Art. I, §8, cl. 18. See 21 U. S. C.
§801(6). However, in order to be “necessary,” the intra-
state ban must be more than “a reasonable means [of]
effectuat[ing] the regulation of interstate commerce.”
Brief for Petitioners 14; see ante, at 19 (majority opinion)
(employing rational-basis review). It must be “plainly
adapted” to regulating interstate marijuana trafficking—
in other words, there must be an “obvious, simple, and
direct relation” between the intrastate ban and the regula-
tion of interstate commerce. Sabri v. United States, 541
U. S. 600, 613 (2004) (THOMAS, J., concurring in judgment);
see also United States v. Dewitt, 9 Wall. 41, 44 (1870) (find-
ing ban on intrastate sale of lighting oils not “appropriate
and plainly adapted means for carrying into execution”
 Cite as: 545 U. S. ____ (2005) 5

THOMAS, J., dissenting

Congress’ taxing power).
On its face, a ban on the intrastate cultivation, posses-
sion and distribution of marijuana may be plainly adapted
to stopping the interstate flow of marijuana. Unregulated
local growers and users could swell both the supply and
the demand sides of the interstate marijuana market,
making the market more difficult to regulate. Ante, at 9–
10, 19 (majority opinion). But respondents do not chal-
lenge the CSA on its face. Instead, they challenge it as
applied to their conduct. The question is thus whether the
intrastate ban is “necessary and proper” as applied to
medical marijuana users like respondents.3
Respondents are not regulable simply because they
belong to a large class (local growers and users of mari-
juana) that Congress might need to reach, if they also
belong to a distinct and separable subclass (local growers
and users of state-authorized, medical marijuana) that
does not undermine the CSA’s interstate ban. Ante, at 6–7
(O’CONNOR, J., dissenting). The Court of Appeals found
that respondents’ “limited use is distinct from the broader
illicit drug market,” because “th[eir] medicinal marijuana
. . . is not intended for, nor does it enter, the stream of
commerce.” Raich v. Ashcroft, 352 F. 3d 1222, 1228 (CA9
2003). If that is generally true of individuals who grow
and use marijuana for medical purposes under state law,
then even assuming Congress has “obvious” and “plain”
reasons why regulating intrastate cultivation and posses-
sion is necessary to regulating the interstate drug trade,
none of those reasons applies to medical marijuana pa-
tients like Monson and Raich.
——————
3 Because respondents do not challenge on its face the CSA’s ban on

marijuana, 21 U. S. C. §§841(a)(1), 844(a), our adjudication of their as-
applied challenge casts no doubt on this Court’s practice in United
States v. Lopez, 514 U. S. 549 (1995), and United States v. Morrison, 529
U. S. 598 (2000). In those cases, we held that Congress, in enacting the
statutes at issue, had exceeded its Article I powers.
6 GONZALES v. RAICH

THOMAS, J., dissenting

California’s Compassionate Use Act sets respondents’
conduct apart from other intrastate producers and users of
marijuana. The Act channels marijuana use to “seriously
ill Californians,” Cal. Health & Safety Code Ann.
§11362.5(b)(1)(A) (West Supp. 2005), and prohibits “the
diversion of marijuana for nonmedical purposes,”
§11362.5(b)(2).4 California strictly controls the cultivation
and possession of marijuana for medical purposes. To be
eligible for its program, California requires that a patient
have an illness that cannabis can relieve, such as cancer,
AIDS, or arthritis, §11362.5(b)(1)(A), and that he obtain a
physician’s recommendation or approval, §11362.5(d).
Qualified patients must provide personal and medical
information to obtain medical identification cards, and
there is a statewide registry of cardholders. §§11362.715–
.76. Moreover, the Medical Board of California has issued
guidelines for physicians’ cannabis recommendations, and
it sanctions physicians who do not comply with the guide-
lines. See, e.g., People v. Spark, 121 Cal. App. 4th 259,
263, 16 Cal. Rptr. 3d 840, 843 (2004).
This class of intrastate users is therefore distinguish-
able from others. We normally presume that States en-
force their own laws, Riley v. National Federation of Blind
of N. C., Inc., 487 U. S. 781, 795 (1988), and there is no
reason to depart from that presumption here: Nothing
suggests that California’s controls are ineffective. The scant
evidence that exists suggests that few people—the vast
majority of whom are aged 40 or older—register to use
medical marijuana. General Accounting Office, Marijuana:
Early Experiences with Four States’ Laws That Allow Use
for Medical Purposes 22–23 (Rep. No. 03–189, Nov. 2002),
http://www.gao.gov/new.items/d01389.pdf (all Internet
——————
4 Other
States likewise prohibit diversion of marijuana for nonmedi-
cal purposes. See, e.g., Colo. Const., Art. XVIII, §14(2)(d); Nev. Rev.
Stat. §§453A.300(1)(e)–(f) (2003); Ore. Rev. Stat. §§475.316(1)(c)–(d)
(2003).
 Cite as: 545 U. S. ____ (2005) 7

THOMAS, J., dissenting

materials as visited on June 3, 2005, and available in
Clerk of Court’s case file). In part because of the low
incidence of medical marijuana use, many law enforce-
ment officials report that the introduction of medical
marijuana laws has not affected their law enforcement
efforts. Id., at 32.
These controls belie the Government’s assertion that
placing medical marijuana outside the CSA’s reach “would
prevent effective enforcement of the interstate ban on
drug trafficking.” Brief for Petitioners 33. Enforcement of
the CSA can continue as it did prior to the Compassionate
Use Act. Only now, a qualified patient could avoid arrest
or prosecution by presenting his identification card to law
enforcement officers. In the event that a qualified patient
is arrested for possession or his cannabis is seized, he
could seek to prove as an affirmative defense that, in
conformity with state law, he possessed or cultivated small
quantities of marijuana intrastate solely for personal
medical use. People v. Mower, 28 Cal. 4th 457, 469–470,
49 P. 3d 1067, 1073–1075 (2002); People v. Trippet, 56 Cal.
App. 4th 1532, 1549 (1997). Moreover, under the CSA,
certain drugs that present a high risk of abuse and addic-
tion but that nevertheless have an accepted medical use—
drugs like morphine and amphetamines—are available by
prescription. 21 U. S. C. §§812(b)(2)(A)–(B); 21 CFR
§1308.12 (2004). No one argues that permitting use of
these drugs under medical supervision has undermined
the CSA’s restrictions.
But even assuming that States’ controls allow some
seepage of medical marijuana into the illicit drug market,
there is a multibillion-dollar interstate market for mari-
juana. Executive Office of the President, Office of Nat.
Drug Control Policy, Marijuana Fact Sheet 5 (Feb. 2004),
http://www.whitehousedrugpolicy.gov/publications/factsht/
marijuana/index.html. It is difficult to see how this vast
market could be affected by diverted medical cannabis, let
alone in a way that makes regulating intrastate medical
8 GONZALES v. RAICH

THOMAS, J., dissenting

marijuana obviously essential to controlling the interstate
drug market.
To be sure, Congress declared that state policy would
disrupt federal law enforcement. It believed the across-
the-board ban essential to policing interstate drug traffick-
ing. 21 U. S. C. §801(6). But as JUSTICE O’CONNOR points
out, Congress presented no evidence in support of its
conclusions, which are not so much findings of fact as
assertions of power. Ante, at 13–14 (dissenting opinion).
Congress cannot define the scope of its own power merely
by declaring the necessity of its enactments.
In sum, neither in enacting the CSA nor in defending its
application to respondents has the Government offered
any obvious reason why banning medical marijuana use is
necessary to stem the tide of interstate drug trafficking.
Congress’ goal of curtailing the interstate drug trade
would not plainly be thwarted if it could not apply the
CSA to patients like Monson and Raich. That is, unless
Congress’ aim is really to exercise police power of the sort
reserved to the States in order to eliminate even the intra-
state possession and use of marijuana.
2
Even assuming the CSA’s ban on locally cultivated and
consumed marijuana is “necessary,” that does not mean it
is also “proper.” The means selected by Congress to regu-
late interstate commerce cannot be “prohibited” by, or
inconsistent with the “letter and spirit” of, the Constitution.
McCulloch, 4 Wheat., at 421.
In Lopez, I argued that allowing Congress to regulate
intrastate, noncommercial activity under the Commerce
Clause would confer on Congress a general “police power”
over the Nation. 514 U. S., at 584, 600 (concurring opin-
ion). This is no less the case if Congress ties its power to
the Necessary and Proper Clause rather than the Com-
merce Clause. When agents from the Drug Enforcement
 Cite as: 545 U. S. ____ (2005) 9

THOMAS, J., dissenting

Administration raided Monson’s home, they seized six
cannabis plants. If the Federal Government can regulate
growing a half-dozen cannabis plants for personal con-
sumption (not because it is interstate commerce, but
because it is inextricably bound up with interstate com-
merce), then Congress’ Article I powers—as expanded by
the Necessary and Proper Clause—have no meaningful
limits. Whether Congress aims at the possession of drugs,
guns, or any number of other items, it may continue to
“appropria[te] state police powers under the guise of regu-
lating commerce.” United States v. Morrison, 529 U. S. 598,
627 (2000) (THOMAS, J., concurring).
Even if Congress may regulate purely intrastate activity
when essential to exercising some enumerated power, see
Dewitt, 9 Wall., at 44; but see Barnett, The Original Mean-
ing of the Necessary and Proper Clause, 6 U. Pa. J. Const.
L. 183, 186 (2003) (detailing statements by Founders that
the Necessary and Proper Clause was not intended to
expand the scope of Congress’ enumerated powers), Con-
gress may not use its incidental authority to subvert basic
principles of federalism and dual sovereignty. Printz v.
United States, 521 U. S. 898, 923–924 (1997); Alden v.
Maine, 527 U. S. 706, 732–733 (1999); Garcia v. San Anto-
nio Metropolitan Transit Authority, 469 U. S. 528, 585
(1985) (O’CONNOR, J., dissenting); The Federalist No. 33, pp.
204–205 (J. Cooke ed. 1961) (A. Hamilton) (hereinafter The
Federalist).
Here, Congress has encroached on States’ traditional
police powers to define the criminal law and to protect the
health, safety, and welfare of their citizens.5 Brecht v.
——————
5 In fact, the Anti-Federalists objected that the Necessary and Proper

Clause would allow Congress, inter alia, to “constitute new Crimes, . . .
and extend [its] Power as far as [it] shall think proper; so that the State
Legislatures have no Security for the Powers now presumed to remain
to them; or the People for their Rights.” Mason, Objections to the
Constitution Formed by the Convention (1787), in 2 The Complete Anti-
10 GONZALES v. RAICH

THOMAS, J., dissenting

Abrahamson, 507 U. S. 619, 635 (1993); Hillsborough
County v. Automated Medical Laboratories, Inc., 471 U. S.
707, 719 (1985). Further, the Government’s rationale—that
it may regulate the production or possession of any commod-
ity for which there is an interstate market—threatens to
remove the remaining vestiges of States’ traditional police
powers. See Brief for Petitioners 21–22; cf. Ehrlich, The
Increasing Federalization of Crime, 32 Ariz. St. L. J. 825,
826, 841 (2000) (describing both the relative recency of a
large percentage of federal crimes and the lack of a relation-
ship between some of these crimes and interstate com-
merce). This would convert the Necessary and Proper
Clause into precisely what Chief Justice Marshall did not
envision, a “pretext . . . for the accomplishment of objects
not intrusted to the government.” McCulloch, supra, at
423.
II
The majority advances three reasons why the CSA is a
legitimate exercise of Congress’ authority under the Com-
merce Clause: First, respondents’ conduct, taken in the
aggregate, may substantially affect interstate commerce,
ante, at 19; second, regulation of respondents’ conduct is
essential to regulating the interstate marijuana market,
ante, at 21–22; and, third, regulation of respondents’
——————
Federalist 11, 12–13 (H. Storing ed. 1981) (emphasis added). Hamilton
responded that these objections were gross “misrepresentation[s].” The
Federalist No. 33, at 204. He termed the Clause “perfectly harmless,”
for it merely confirmed Congress’ implied authority to enact laws in
exercising its enumerated powers. Id., at 205; see also Lopez, 514 U. S.,
at 597, n. 6 (THOMAS, J., concurring) (discussing Congress’ limited ability
to establish nationwide criminal prohibitions); Cohens v. Virginia, 6
Wheat. 264, 426–428 (1821) (finding it “clear that [C]ongress cannot
punish felonies generally,” except in areas over which it possesses plenary
power). According to Hamilton, the Clause was needed only “to guard
against cavilling refinements” by those seeking to cripple federal power.
The Federalist No. 33, at 205; id., No. 44, at 303–304 (J. Madison).
 Cite as: 545 U. S. ____ (2005) 11

THOMAS, J., dissenting

conduct is incidental to regulating the interstate mari-
juana market, ante, at 19–20. JUSTICE O’CONNOR ex-
plains why the majority’s reasons cannot be reconciled
with our recent Commerce Clause jurisprudence. The
majority’s justifications, however, suffer from even more
fundamental flaws.
A
The majority holds that Congress may regulate intra-
state cultivation and possession of medical marijuana
under the Commerce Clause, because such conduct argua-
bly has a substantial effect on interstate commerce. The
majority’s decision is further proof that the “substantial
effects” test is a “rootless and malleable standard” at odds
with the constitutional design. Morrison, supra, at 627
(THOMAS, J., concurring).
The majority’s treatment of the substantial effects test
is rootless, because it is not tethered to either the Com-
merce Clause or the Necessary and Proper Clause. Under
the Commerce Clause, Congress may regulate interstate
commerce, not activities that substantially affect inter-
state commerce—any more than Congress may regulate
activities that do not fall within, but that affect, the sub-
jects of its other Article I powers. Lopez, supra, at 589
(THOMAS, J., concurring). Whatever additional latitude
the Necessary and Proper Clause affords, supra, at 9–10,
the question is whether Congress’ legislation is essential
to the regulation of interstate commerce itself—not
whether the legislation extends only to economic activities
that substantially affect interstate commerce. Supra, at 4;
ante, at 5 (SCALIA, J., concurring in judgment).
The majority’s treatment of the substantial effects test
is malleable, because the majority expands the relevant
conduct. By defining the class at a high level of generality
(as the intrastate manufacture and possession of mari-
juana), the majority overlooks that individuals authorized
12 GONZALES v. RAICH

THOMAS, J., dissenting

by state law to manufacture and possess medical mari-
juana exert no demonstrable effect on the interstate drug
market. Supra, at 7–8. The majority ignores that
whether a particular activity substantially affects inter-
state commerce—and thus comes within Congress’ reach
on the majority’s approach—can turn on a number of
objective factors, like state action or features of the regu-
lated activity itself. Ante, at 6–7 (O’CONNOR, J., dissent-
ing). For instance, here, if California and other States are
effectively regulating medical marijuana users, then these
users have little effect on the interstate drug trade.6
The substantial effects test is easily manipulated for
another reason. This Court has never held that Congress
can regulate noneconomic activity that substantially
affects interstate commerce. Morrison, 529 U. S., at 613
(“[T]hus far in our Nation’s history our cases have upheld
Commerce Clause regulation of intrastate activity only
where that activity is economic in nature” (emphasis
added)); Lopez, supra, at 560. To evade even that modest
——————
6 Remarkably, the majority goes so far as to declare this question

irrelevant. It asserts that the CSA is constitutional even if California’s
current controls are effective, because state action can neither expand
nor contract Congress’ powers. Ante, at 27, n. 38. The majority’s
assertion is misleading. Regardless of state action, Congress has the
power to regulate intrastate economic activities that substantially
affect interstate commerce (on the majority’s view) or activities that are
necessary and proper to effectuating its commerce power (on my view).
But on either approach, whether an intrastate activity falls within the
scope of Congress’ powers turns on factors that the majority is unwill-
ing to confront. The majority apparently believes that even if States
prevented any medical marijuana from entering the illicit drug market,
and thus even if there were no need for the CSA to govern medical
marijuana users, we should uphold the CSA under the Commerce
Clause and the Necessary and Proper Clause. Finally, to invoke the
Supremacy Clause, as the majority does, ibid., is to beg the question.
The CSA displaces California’s Compassionate Use Act if the CSA is
constitutional as applied to respondents’ conduct, but that is the very
question at issue.
 Cite as: 545 U. S. ____ (2005) 13

THOMAS, J., dissenting

restriction on federal power, the majority defines economic
activity in the broadest possible terms as the “ ‘the produc-
tion, distribution, and consumption of commodities.’ ”7
Ante, at 23 (quoting Webster’s Third New International
Dictionary 720 (1966) (hereinafter Webster’s 3d). This
carves out a vast swath of activities that are subject to
federal regulation. See ante, at 8–9 (O’CONNOR, J., dis-
senting). If the majority is to be taken seriously, the
Federal Government may now regulate quilting bees,
clothes drives, and potluck suppers throughout the 50
States. This makes a mockery of Madison’s assurance to
the people of New York that the “powers delegated” to the
Federal Government are “few and defined,” while those of
the States are “numerous and indefinite.” The Federalist
No. 45, at 313 (J. Madison).
Moreover, even a Court interested more in the modern
than the original understanding of the Constitution ought
to resolve cases based on the meaning of words that are
actually in the document. Congress is authorized to regu-
late “Commerce,” and respondents’ conduct does not qual-
ify under any definition of that term.8 The majority’s
opinion only illustrates the steady drift away from the text
of the Commerce Clause. There is an inexorable expan-
——————
7 Other dictionaries do not define the term “economic” as broadly as
the majority does. See, e.g., The American Heritage Dictionary of the
English Language 583 (3d ed. 1992) (defining “economic” as “[o]f or
relating to the production, development, and management of material
wealth, as of a country, household, or business enterprise” (emphasis
added)). The majority does not explain why it selects a remarkably
expansive 40-year-old definition.
8 See, e.g., id., at 380 (“[t]he buying and selling of goods, especially on

a large scale, as between cities or nations”); The Random House Dic-
tionary of the English Language 411 (2d ed. 1987) (“an interchange of
goods or commodities, esp. on a large scale between different countries
. . . or between different parts of the same country”); Webster’s 3d 456
(“the exchange or buying and selling of commodities esp. on a large
scale and involving transportation from place to place”).
14 GONZALES v. RAICH

THOMAS, J., dissenting

sion from “ ‘commerce,’ ” ante, at 1, to “commercial” and
“economic” activity, ante, at 20, and finally to all “produc-
tion, distribution, and consumption” of goods or services
for which there is an “established . . . interstate market,”
ante, at 23. Federal power expands, but never contracts,
with each new locution. The majority is not interpreting
the Commerce Clause, but rewriting it.
The majority’s rewriting of the Commerce Clause seems
to be rooted in the belief that, unless the Commerce
Clause covers the entire web of human activity, Congress
will be left powerless to regulate the national economy
effectively. Ante, at 15–16; Lopez, 514 U. S., at 573–574
(KENNEDY, J., concurring). The interconnectedness of
economic activity is not a modern phenomenon unfamiliar
to the Framers. Id., at 590–593 (THOMAS, J., concurring);
Letter from J. Madison to S. Roane (Sept. 2, 1819), in 3
The Founders’ Constitution 259–260 (P. Kurland & R.
Lerner eds. 1987). Moreover, the Framers understood
what the majority does not appear to fully appreciate:
There is a danger to concentrating too much, as well as too
little, power in the Federal Government. This Court has
carefully avoided stripping Congress of its ability to regu-
late interstate commerce, but it has casually allowed the
Federal Government to strip States of their ability to
regulate intrastate commerce—not to mention a host of
local activities, like mere drug possession, that are not
commercial.
One searches the Court’s opinion in vain for any hint of
what aspect of American life is reserved to the States. Yet
this Court knows that “ ‘[t]he Constitution created a Fed-
eral Government of limited powers.’ ” New York v. United
States, 505 U. S. 144, 155 (1992) (quoting Gregory v.
Ashcroft, 501 U. S. 452, 457 (1991)). That is why today’s
decision will add no measure of stability to our Commerce
Clause jurisprudence: This Court is willing neither to
enforce limits on federal power, nor to declare the Tenth
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THOMAS, J., dissenting

Amendment a dead letter. If stability is possible, it is only
by discarding the stand-alone substantial effects test and
revisiting our definition of “Commerce among the several
States.” Congress may regulate interstate commerce—not
things that affect it, even when summed together, unless
truly “necessary and proper” to regulating interstate
commerce.
B
The majority also inconsistently contends that regulat-
ing respondents’ conduct is both incidental and essential
to a comprehensive legislative scheme. Ante, at 19–20,
21–22. I have already explained why the CSA’s ban on
local activity is not essential. Supra, at 7–8. However,
the majority further claims that, because the CSA covers a
great deal of interstate commerce, it “is of no moment” if it
also “ensnares some purely intrastate activity.” Ante, at
19. So long as Congress casts its net broadly over an
interstate market, according to the majority, it is free to
regulate interstate and intrastate activity alike. This
cannot be justified under either the Commerce Clause or
the Necessary and Proper Clause. If the activity is purely
intrastate, then it may not be regulated under the Com-
merce Clause. And if the regulation of the intrastate
activity is purely incidental, then it may not be regulated
under the Necessary and Proper Clause.
Nevertheless, the majority terms this the “pivotal”
distinction between the present case and Lopez and Morri-
son. Ante, at 20. In Lopez and Morrison, the parties
asserted facial challenges, claiming “that a particular
statute or provision fell outside Congress’ commerce power
in its entirety.” Ante, at 20. Here, by contrast, respon-
dents claim only that the CSA falls outside Congress’
commerce power as applied to their individual conduct.
According to the majority, while courts may set aside
whole statutes or provisions, they may not “excise individ-
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THOMAS, J., dissenting

ual applications of a concededly valid statutory scheme.”
Ante, at 20–21; see also Perez v. United States, 402 U. S.
146, 154 (1971); Maryland v. Wirtz, 392 U. S. 183, 192–193
(1968).
It is true that if respondents’ conduct is part of a “class of
activities . . . and that class is within the reach of federal
power,” Perez, supra, at 154 (emphases deleted), then
respondents may not point to the de minimis effect of their
own personal conduct on the interstate drug market,
Wirtz, supra, at 196, n. 27. Ante, at 6 (O’CONNOR, J.,
dissenting). But that begs the question at issue: whether
respondents’ “class of activities” is “within the reach of
federal power,” which depends in turn on whether the
class is defined at a low or a high level of generality.
Supra, at 5. If medical marijuana patients like Monson
and Raich largely stand outside the interstate drug mar-
ket, then courts must excise them from the CSA’s cover-
age. Congress expressly provided that if “a provision [of
the CSA] is held invalid in one of more of its applications,
the provision shall remain in effect in all its valid applica-
tions that are severable.” 21 U. S. C. §901 (emphasis
added); see also United States v. Booker, 543 U. S. ___, ___
(2005) (slip op., at 9, and n. 9) (THOMAS, J., dissenting in
part).
Even in the absence of an express severability provision,
it is implausible that this Court could set aside entire
portions of the United States Code as outside Congress’
power in Lopez and Morrison, but it cannot engage in the
more restrained practice of invalidating particular appli-
cations of the CSA that are beyond Congress’ power. This
Court has regularly entertained as-applied challenges
under constitutional provisions, see United States v.
Raines, 362 U. S. 17, 20–21 (1960), including the Commerce
Clause, see Katzenbach v. McClung, 379 U. S. 294, 295
(1964); Heart of Atlanta Motel, Inc. v. United States, 379
U. S. 241, 249 (1964); Wickard v. Filburn, 317 U. S. 111,
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THOMAS, J., dissenting

113–114 (1942). There is no reason why, when Congress
exceeds the scope of its commerce power, courts may not
invalidate Congress’ overreaching on a case-by-case basis.
The CSA undoubtedly regulates a great deal of interstate
commerce, but that is no license to regulate conduct that
is neither interstate nor commercial, however minor or
incidental.
If the majority is correct that Lopez and Morrison are
distinct because they were facial challenges to “particular
statute[s] or provision[s],” ante, at 20, then congressional
power turns on the manner in which Congress packages
legislation. Under the majority’s reasoning, Congress could
not enact—either as a single-subject statute or as a separate
provision in the CSA—a prohibition on the intrastate pos-
session or cultivation of marijuana. Nor could it enact an
intrastate ban simply to supplement existing drug regula-
tions. However, that same prohibition is perfectly constitu-
tional when integrated into a piece of legislation that
reaches other regulable conduct. Lopez, 514 U. S., at 600–
601 (THOMAS, J., concurring).
Finally, the majority’s view—that because some of the
CSA’s applications are constitutional, they must all be
constitutional—undermines its reliance on the substantial
effects test. The intrastate conduct swept within a general
regulatory scheme may or may not have a substantial
effect on the relevant interstate market. “[O]ne always
can draw the circle broadly enough to cover an activity
that, when taken in isolation, would not have substantial
effects on commerce.” Id., at 600 (THOMAS, J., concurring).
The breadth of legislation that Congress enacts says noth-
ing about whether the intrastate activity substantially
affects interstate commerce, let alone whether it is neces-
sary to the scheme. Because medical marijuana users in
California and elsewhere are not placing substantial
amounts of cannabis into the stream of interstate com-
merce, Congress may not regulate them under the sub-
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THOMAS, J., dissenting

stantial effects test, no matter how broadly it drafts the
CSA.
* * *
The majority prevents States like California from devis-
ing drug policies that they have concluded provide much-
needed respite to the seriously ill. It does so without any
serious inquiry into the necessity for federal regulation or
the propriety of “displac[ing] state regulation in areas of
traditional state concern,” id., at 583 (KENNEDY, J., con-
curring). The majority’s rush to embrace federal power “is
especially unfortunate given the importance of showing
respect for the sovereign States that comprise our Federal
Union.” United States v. Oakland Cannabis Buyers’ Coop-
erative, 532 U. S. 483, 502 (2001) (STEVENS, J., concurring
in judgment). Our federalist system, properly understood,
allows California and a growing number of other States to
decide for themselves how to safeguard the health and
welfare of their citizens. I would affirm the judgment of
the Court of Appeals. I respectfully dissent.