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SJC-12750
COMMONWEALTH vs. JASON J. McCARTHY.
Barnstable. October 2, 2019. - April 16, 2020.
Present (Sitting at Barnstable): Gants, C.J., Lenk, Gaziano,
Lowy, Budd, Cypher, & Kafker, JJ.
Privacy. Constitutional Law, Privacy, Search and seizure,
Standing, Admissions and confessions, Voluntariness of
statement. Search and Seizure, Expectation of privacy,
Electronic surveillance, Motor vehicle. Practice,
Criminal, Motion to suppress, Standing, Admissions and
confessions, Voluntariness of statement. Evidence,
Admissions and confessions, Voluntariness of statement.
Indictment found and returned in the Superior Court
Department on August 31, 2017.
Pretrial motions to suppress evidence were heard by Robert
C. Rufo, J.
An application for leave to prosecute an interlocutory
appeal was allowed by Kafker, J., in the Supreme Judicial Court
for the county of Suffolk, and the case was reported by him.
Paul A. Bogosian for the defendant.
Elizabeth A. Sweeney, Assistant District Attorney, for the
Commonwealth.
David R. Fox, for Digital Recognition Network, Inc., amicus
curiae, submitted a brief.
2
Matthew Spurlock & David Rassoul Rangaviz, Committee for
Public Counsel Services, Ashley Gorski, of New York, Jennifer
Lynch & Andrew Crocker, of California, Jessie J. Rossman,
Matthew R. Segal, & Nathan Freed Wessler, for American Civil
Liberties Union & others, amici curiae, submitted a brief.
GAZIANO, J. While investigating the defendant on suspicion
of drug distribution, police used automatic license plate
readers (ALPRs) on the Bourne and Sagamore bridges to track his
movements. They accessed historical data, which revealed the
number of times he had crossed the bridges over a three-month
period, and also received real-time alerts, one of which led to
his arrest. We must determine whether the use of ALPR
technology in this case constituted a search under the Fourth
Amendment to the United States Constitution or under art. 14 of
the Massachusetts Declaration of Rights.
We conclude that, while the defendant has a
constitutionally protected expectation of privacy in the whole
of his public movements, an interest which potentially could be
implicated by the widespread use of ALPRs, that interest is not
invaded by the limited extent and use of ALPR data in this case.
1. Background. We draw the following from the facts found
by the motion judge, reserving some facts for later discussion.
a. ALPR systems. Automatic license plate readers are
cameras combined with software that allows them to identify and
"read" license plates on passing vehicles. When an ALPR
3
identifies a license plate, it records a photograph of the
plate, the system's interpretation of the license plate number,
and other data, such as the date, time, location, direction of
travel, and travel lane. In Massachusetts, cameras owned and
maintained by the State police feed this information into a
database maintained by the Executive Office of Public Safety and
Security (EOPSS).1 At some point in 2015, the State police
installed fixed camera readers on both sides of the Sagamore and
Bourne bridges. While these cameras are not infallible,2 they
essentially create a comprehensive record of vehicles traveling
onto or off of the Cape.
ALPR systems produce two related types of information:
real-time alerts and historical data. First, individuals with
user credentials can log onto the ALPR system, enter license
plate numbers onto a "hot list," and choose users to be notified
about any new "hits" for that plate number. If a camera in the
ALPR system detects a license plate that matches a number on the
hot list, the system sends an electronic mail message or text
1 According to the amici, private companies also own and
operate automatic license plate reader (ALPR) cameras and share
that data with law enforcement, as do individual homeowners.
Federal and State law enforcement offices, in turn, may share
data with each other.
2 A testifying expert identified weather conditions, warped
or obscured plates, and particularly bad lighting conditions as
factors that might result in the ALPR failing to read a
particular license plate.
4
message to the specified officers. Alert recipients receive an
image of the plate, along with the date, time, location, and
direction of travel. Second, users can search by license plate
number for any historical matches stored in the database. EOPSS
currently has a one-year retention policy for ALPR data.3
The Barnstable police department has adopted the State
police general order setting out various regulations for the use
of ALPR information. See State police General Order No. TRF-11
(July 22, 2014) (Order TRF-11).4
b. The investigation. Through surveillance, several
"controlled buys," and information from four confidential
informants, the Barnstable police developed substantial evidence
that a codefendant in this case was distributing heroin from his
residence. During that surveillance, they observed a black
Hyundai vehicle appear briefly at the codefendant's residence.
3 Aside from any changes to retention policy or failure to
implement purging according to the policy, electronic mail
messages sent after a real-time alert may be retained longer
than one year, indeed indefinitely, on the recipient's server,
as was the case here.
4 State police General Order No. TRF-11 (July 22, 2014)
(Order TRF-11) requires, inter alia, that only trained,
specially designated users may access the system; that the "ALPR
System and information shall be . . . [a]ccessed and used only
for official and legitimate law enforcement purpose"; and that
prior to initiating a stop based on an ALPR hit or alert, the
officer must verify visually the alphanumeric characters on the
license plate and verify the status of the plate through one of
various databases.
5
After further surveillance, and a tip from a confidential
informant, police observed the defendant driving the same
vehicle, and they began to suspect that he was supplying heroin
to his codefendant.
On February 1, 2017, Barnstable police added the license
plate number of the black Hyundai to the ALPR hot list, and
specified officers to be notified when it was detected crossing
the Bourne or Sagamore bridges. On February 8, 2017, several
police officers received an alert that the Hyundai had been
driven over the Sagamore Bridge onto Cape Cod. Officers
subsequently traveled to the codefendant's house and then
followed him to Shallow Pond Road in Centerville. At the same
time, another officer found the defendant after he drove onto
the Cape and followed him to Shallow Pond Road. The officers
watched the defendant and the codefendant meet, but no physical
exchange was observed. Both vehicles left after approximately
thirty seconds.
Police also generated a spreadsheet indicating every time
that the Hyundai had passed over the Bourne and Sagamore bridges
between December 1, 2016, and February 12, 2017. The
spreadsheet contained the dates, times, directions, and specific
lanes that the Hyundai had traveled on the bridges. The ALPR
spreadsheet showed that the vehicle traveled onto Cape Cod on
eight days in February, twenty-one days in January, and nineteen
6
days in December. On multiple of these days, the defendant made
more than one trip on the same day. This appeared consistent
with the police theory that the defendant routinely was bringing
heroin onto the Cape for distribution by his codefendant.
On February 22, 2017, Barnstable police received another
alert that the Hyundai had traveled over the Sagamore Bridge
onto Cape Cod. Police again followed both the defendant and the
codefendant as they drove to Shallow Pond Road. The officers
observed a meeting, but did not see an exchange of objects.
Both vehicles departed thirty seconds later. This time, police
stopped both vehicles on suspicion that a drug transaction had
taken place.
After stopping the codefendant, police handcuffed him, read
him his Miranda rights, and questioned him at the side of the
road. He made incriminating statements, and officers found
heroin on his person. Police also ordered the defendant out of
his vehicle, handcuffed him, and read him his Miranda rights.
The motion judge found that the defendant was under arrest at
the moment that he was ordered out of the Hyundai and
handcuffed.
At the police station, the defendant waived his Miranda
rights and made various incriminating statements. Officers also
seized two cellular telephones and United States currency from
the defendant's person. The defendant's brother brought more
7
money to pay the bail for the defendant, but police seized
almost all of the cash on the belief that it was the proceeds of
illegal drug activity.
The defendant filed motions to suppress the ALPR data and
the fruits of the arrest. A Superior Court judge held an
evidentiary hearing and then denied the motions. The defendant
then filed an application for leave to pursue an interlocutory
appeal in the county court, pursuant to Mass. R. Crim.
P. 15 (a) (2), as appearing in 474 Mass. 1501 (2016); the single
justice allowed the appeal to proceed in this court.
2. Discussion. "In reviewing a decision on a motion to
suppress, we accept the judge's subsidiary findings absent clear
error but conduct an independent review of [the] ultimate
findings and conclusions of law" (quotations and citation
omitted). Commonwealth v. Jones-Pannell, 472 Mass. 429, 431
(2015). Here, reviewing the judge's conclusions of law requires
us to determine, among other things, whether the use of ALPR
technology by police constitutes a search under the Fourth
Amendment or art. 14.
a. ALPRs and constitutional search protections. Under
both the Fourth Amendment and art. 14, a search implicates
constitutional protections when the government "intrudes on a
person's reasonable expectation of privacy" (citation omitted).
Commonwealth v. Almonor, 482 Mass. 35, 40 (2019). "An
8
individual has a reasonable expectation of privacy where (i) the
individual has manifested a subjective expectation of privacy in
the object of the search, and (ii) society is willing to
recognize that expectation as reasonable" (quotations and
citation omitted).5 Commonwealth v. Johnson, 481 Mass. 710, 715,
cert. denied, 140 S. Ct. 247 (2019). See Katz v. United States,
389 U.S. 347, 361 (1967) (Harlan, J., concurring).
The constitutional jurisprudence governing the
technological surveillance of public space has developed rapidly
in the last decade. To place the current situation in the
proper context, it is necessary to review these developments and
their underlying reasoning at some length.
i. Expectations of privacy and technology. As this court
and the United States Supreme Court interpret society's
reasonable expectations of privacy over time, the courts'
overarching goal is to "assure [the] preservation of that degree
5 In this case, the judge did not find explicitly that the
defendant had manifested a subjective expectation of privacy.
We infer from the undisputed record, however, that the defendant
manifested a subjective expectation of privacy in his location
by choosing to meet his codefendant in a quiet residential area.
See Commonwealth v. Fulgiam, 477 Mass. 20, 33, cert. denied, 138
S. Ct. 330 (2017) (concluding that subjective prong was
satisfied based on record). See, e.g., United States v. Moore-
Bush, 381 F. Supp. 3d 139, 143 (D. Mass. 2019) ("the Court
infers from their choice of neighborhood that they subjectively
expected that their and their houseguests' comings and goings
over the course of eight months would not be surreptitiously
surveilled").
9
of privacy against government that existed when the Fourth
Amendment [and art. 14 were] adopted." Almonor, 482 Mass. at 54
(Lenk, J., concurring), quoting Carpenter v. United States, 138
S. Ct. 2206, 2214 (2018). We have recognized the difficulty of
this enterprise as developing technology places "extraordinarily
powerful surveillance tool[s]" in the hands of police. Almonor,
supra at 46. See Johnson, 481 Mass. at 716. While
acknowledging the usefulness of these tools for crime detection,
"both this court and the United States Supreme Court have been
careful to guard against the 'power of technology to shrink the
realm of guaranteed privacy' by emphasizing that privacy rights
'cannot be left at the mercy of advancing technology but rather
must be preserved and protected as new technologies are adopted
and applied by law enforcement.'" Almonor, supra at 41, quoting
Johnson, supra. See Kyllo v. United States, 533 U.S. 27, 34
(2001). See also Olmstead v. United States, 277 U.S. 438, 473
(1928) (Brandeis, J., dissenting) (noting that courts must be
vigilant to guard against "[s]ubtler and more far-reaching means
of invading privacy [that] have become available to the
government").
Like the Supreme Court, this court is guided "by historical
understandings of what was deemed an unreasonable search and
seizure when [the Constitutions were] adopted." See Almonor,
482 Mass. at 43, citing Carpenter, 138 S. Ct. at 2214. These
10
historical understandings include the basic purposes underlying
the adoption of art. 14 and, later, the Fourth Amendment. See
Almonor, supra, quoting Jenkins v. Chief Justice of the Dist.
Court Dep't, 416 Mass. 221, 229 (1993) ("we construe [art. 14]
in light of the circumstances under which it was framed, the
causes leading to its adoption, the imperfections hoped to be
remedied, and the ends designed to be accomplished"). See also
Carpenter, supra at 2213. More specifically, we have recognized
that the underlying purposes of both art. 14 and the Fourth
Amendment are the need to "secure the privacies of life against
arbitrary power," and to "place obstacles in the way of a too
permeating police surveillance." Almonor, supra at 53 (Lenk,
J., concurring), quoting Carpenter, supra at 2214. Both warrant
further explanation in the context of emerging technology.
A. Arbitrary power. The framers had first-hand experience
with abuses of arbitrary power under British rule. Our cases
acknowledge that they wrote constitutional search protections in
"response to the reviled 'general warrants' and 'writs of
assistance' of the colonial era, which allowed British officers
to rummage through homes in an unrestrained search for evidence
of criminal activity." See Carpenter, 138 S. Ct. at 2213,
quoting Riley v. California, 573 U.S. 373, 403 (2014). See also
Commonwealth v. Blood, 400 Mass. 61, 71 (1987). The
surveillance implications of new technologies must be
11
scrutinized carefully, lest scientific advances give police
surveillance powers akin to these general warrants. Just as
police are not permitted to rummage unrestrained through one's
home, so too constitutional safeguards prevent warrantless
rummaging through the complex digital trails and location
records created merely by participating in modern society. See,
e.g., Almonor, 482 Mass. at 46 (police causing cellular
telephone to reveal real-time location contravenes reasonable
expectation of privacy); Commonwealth v. Augustine, 467 Mass.
230, 255 (2014), S.C., 470 Mass. 837 (2015) (reasonable
expectation of privacy exists in cellular site location
information [CSLI]6). See also Carpenter, supra at 2217 ("A
person does not surrender all Fourth Amendment protection by
venturing into the public sphere").
B. Permeating police presence. As the Supreme Court made
clear in Carpenter, courts analyzing the constitutional
implications of new surveillance technologies also should be
guided by the founders' intention "to place obstacles in the way
of a too permeating police surveillance." Carpenter, 138 S. Ct.
at 2214, quoting United States v. Di Re, 332 U.S. 581, 595
6 Cellular site location information "refers to a cellular
telephone service record or records that contain information
identifying the base station towers and sectors that receive
transmissions from a [cellular] telephone" (citation omitted).
Commonwealth v. Estabrook, 472 Mass. 852, 853 n.2 (2015).
12
(1948). Specifically, both this court and the Supreme Court
have recognized how advancing technology undercuts traditional
checks on an overly pervasive police presence because it (1) is
not limited by the same practical constraints that heretofore
effectively have limited long-running surveillance, (2) proceeds
surreptitiously, and (3) gives police access to categories of
information previously unknowable.
As Justice Alito wrote in Jones, "[i]n the pre-computer
age, the greatest protections of privacy were neither
constitutional nor statutory, but practical. Traditional
surveillance for any extended period of time was difficult and
costly and therefore rarely undertaken." United States v.
Jones, 565 U.S. 400, 429 (2012) (Alito, J., concurring). The
continuous, tireless, effortless, and absolute surveillance of
the digital age contravenes expectations of privacy that are
rooted in these historical and practical limitations. For this
reason, when the duration of digital surveillance drastically
exceeds what would have been possible with traditional law
enforcement methods, that surveillance constitutes a search
under art. 14. See, e.g., Augustine, 467 Mass. at 253.
In addition, the surreptitious nature of digital
surveillance removes a natural obstacle to too permeating a
police presence by hiding the extent of that surveillance.
Resource constraints aside, we imagine Massachusetts residents
13
would object were the police continuously to track every
person's public movements by traditional surveillance methods,
absent any suspicion at all. Justice Sotomayor summed up these
first two concerns in a discussion of global positioning system
(GPS)7 monitoring: "because [it] is cheap in comparison to
conventional surveillance techniques and, by design, proceeds
surreptitiously, it evades the ordinary checks that constrain
abusive law enforcement practices: 'limited police resources
and community hostility'" (citation omitted). Jones, 565 U.S.
at 415–416 (Sotomayor, J., concurring).
Finally, new surveillance techniques risk creating too
permeating a police presence by giving police access to "a
category of information otherwise unknowable." Carpenter, 138
S. Ct. at 2218. For example, with CSLI data "the Government can
now travel back in time to retrace a person's whereabouts . . .
[and] police need not even know in advance whether they want to
follow a particular individual, or when. Whoever the suspect
turns out to be, he has effectively been tailed every moment of
every day for five years . . . ." Id. See Augustine, 467 Mass.
7 A global positioning system (GPS) tracking system "allows
police to monitor and record the location of a vehicle [or an
individual] without the [target]'s knowledge" by ascertaining
the target's location via communication with satellites, and
then transmitting that location to a computer system that stores
it electronically. Commonwealth v. Connolly, 454 Mass. 808, 812
(2009).
14
at 254. Likewise, in Almonor, 482 Mass. at 46, this court
considered the capability of police to "ping" a cellular
telephone, causing it to reveal its real-time location data, and
observed that "[t]his extraordinarily powerful surveillance tool
finds no analog in the traditional surveillance methods of law
enforcement."
These historical understandings inform our analysis as we
apply the test that originated more than fifty years ago in
Katz, 389 U.S. at 361 (Harlan, J., concurring), to determine
whether the collection and use of ALPR data constitutes a
search.
ii. Searches in public. This founding-era guidance has
aided courts, even as technological advances in the surveillance
of public space have posed difficult questions to courts under
the "reasonable expectation of privacy" framework established in
Katz. The tension derives from two contrasting sentences
contained in Katz itself. First, Katz states that "[w]hat a
person knowingly exposes to the public, even in his own home or
office, is not a subject of Fourth Amendment protection." Katz,
389 U.S. at 351. For this reason, "[w]hether an expectation of
privacy is reasonable depends in large part upon whether that
expectation relates to information that has been exposed to the
public" (alteration, quotation, and citation omitted). United
States v. Maynard, 615 F.3d 544, 558 (D.C. Cir. 2010), aff'd in
15
part sub nom. Jones, 565 U.S. 400. On the other hand, "[a]
person does not surrender all Fourth Amendment protection by
venturing into the public sphere." Carpenter, 138 S. Ct.
at 2217. For "what [someone] seeks to preserve as private, even
in an area accessible to the public, may be constitutionally
protected." Katz, supra. See id. at 354 (constitutionally
protected privacy interest in contents of telephone conversation
made from public telephone booth). In short, while the Fourth
Amendment and art. 14 "protect[] people, not places," whether
something is knowingly exposed to the public remains a
touchstone in determining the reasonableness of a person's
expectation of privacy. Id. at 351. See Augustine, 467 Mass.
at 252; Commonwealth v. Billings, 42 Mass. App. Ct. 261, 265
(1997) (listing constitutional nonsearches based on knowing
exposure principle).
A. What is knowingly exposed. Under this doctrine, police
observation of the exterior of an automobile is not a search
because it is "knowingly exposed." See New York v. Class, 475
U.S. 106, 114 (1986) ("The exterior of a car, of course, is
thrust into the public eye, and thus to examine it does not
constitute a 'search'"). In Massachusetts, this reasoning
extends quite naturally to license plates. In Commonwealth v.
Starr, 55 Mass. App. Ct. 590, 591 (2001), a police officer saw a
license plate on an automobile, located the plate number in a
16
police database, and stopped the vehicle because the plates were
registered to a different vehicle. Relying on the knowing
exposure principle of Katz, the court held that the defendant
had no reasonable expectation of privacy that would prevent an
officer from examining his license plate. Starr, supra at 593-
594.8
In United States v. Knotts, 460 U.S. 276, 285 (1983), the
Supreme Court applied the logic of "what is knowingly exposed"
to sanction the warrantless use of a radio "beeper"9 to assist
police in tracking a vehicle on a single journey.
"A person traveling in an automobile on public
thoroughfares has no reasonable expectation of privacy
in his movements from one place to another. When [the
codefendant] traveled over the public streets he
voluntarily conveyed to anyone who wanted to look the
fact that he was traveling over particular roads in a
particular direction, the fact of whatever stops he
made, and the fact of his final destination when he
exited from public roads onto private property."
Id. at 281–282. In so holding, the Knotts Court dismissed the
defendant's claim that, should he lose his case, "twenty-four
Massachusetts requires that license plates be "displayed
8
conspicuously," G. L. c. 90, § 6, and the failure to do so can
result in fines or imprisonment, see G. L. c. 90, § 23. These
requirements support the contention that there is no objectively
reasonable expectation of privacy in a license plate number, the
very purpose of which is to identify the vehicle to the
government.
"A beeper is a radio transmitter, usually battery
9
operated, which emits periodic signals that can be picked up by
a radio receiver." United States v. Knotts, 460 U.S. 276, 277
(1983).
17
hour surveillance of any citizen of this country will be
possible, without judicial knowledge or supervision." Id.
at 283. The court went on to note, however, that "if such
dragnet-type law enforcement practices as respondent envisions
should eventually occur, there will be time enough then to
determine whether different constitutional principles may be
applicable." Id. at 284.
In this distinction, we recognize precisely the question
posed by this case: whether Knotts, Starr, and the "knowing
exposure" principle of Katz control, as the Commonwealth
contends, or whether different constitutional principles apply,
as the defendant argues. To answer, we must look to those cases
of emerging surveillance technology where we indeed have
determined that different constitutional principles govern.
B. Mosaic theory. When new technologies drastically
expand police surveillance of public space, both the United
States Supreme Court and this court have recognized a privacy
interest in the whole of one's public movements. See Carpenter,
138 S. Ct. at 2217 ("individuals have a reasonable expectation
of privacy in the whole of their physical movements"); Johnson,
481 Mass. at 716; Augustine, 467 Mass. at 248-249; Commonwealth
v. Rousseau, 465 Mass. 372, 382 (2013).
The question first emerged in the context of a GPS device
affixed to a suspect's vehicle. We ultimately concluded,
18
consistent with Supreme Court precedent, that "the government's
contemporaneous electronic monitoring of one's comings and
goings in public places invades one's reasonable expectation of
privacy." Rousseau, 465 Mass. at 382. Next, in cases
addressing police access to CSLI, both this court and the
Supreme Court reaffirmed the same principle -- that it is
objectively reasonable for individuals to expect to be free from
sustained electronic monitoring of their public movements. See
Augustine, 467 Mass. at 247-248. See also Carpenter, 138 S. Ct.
at 2219.
Both courts reached these conclusions, in part, by
distinguishing the relatively primitive beeper used in Knotts
from the encyclopedic, effortless collection of CSLI and GPS
data. See Augustine, 467 Mass. at 252 ("There is no real
question that the government, without securing a warrant, may
use electronic devices to monitor an individual's movements in
public to the extent that the same result could be achieved
through visual surveillance" [emphasis added]). See also
Carpenter, 138 S. Ct. at 2215, 2218 (distinguishing
"rudimentary" beeper used in Knotts to track single "discrete
automotive journey" from use of CSLI, which achieves "near
perfect surveillance, as if [the government] had attached an
ankle monitor to the phone's user").
19
Essentially, these cases articulate an aggregation
principle for the technological surveillance of public conduct,
sometimes referred to as the mosaic theory.10 When collected for
a long enough period, "the cumulative nature of the information
collected implicates a privacy interest on the part of the
individual who is the target of the tracking." Augustine, 467
Mass. at 253. See Jones, 565 U.S. at 416 (Sotomayor, J.,
concurring) ("when considering the existence of a reasonable
societal expectation of privacy in the sum of one's public
movements . . . I would ask whether people reasonably expect
that their movements will be recorded and aggregated in a manner
that enables the Government to ascertain, more or less at will,
their political and religious beliefs, sexual habits, and so on"
[emphasis added]). A recent case in the United States District
Court for the District of Massachusetts summarized the idea
succinctly: "Although these activities, taken one by one, may
not give rise to a reasonable expectation of privacy . . . , the
10See, e.g., Kerr, The Mosaic Theory of the Fourth
Amendment, 111 Mich. L. Rev. 311, 320 (2012) ("The mosaic theory
requires courts to apply the Fourth Amendment search doctrine to
government conduct as a collective whole rather than in isolated
steps. Instead of asking if a particular act is a search, the
mosaic theory asks whether a series of acts that are not
searches in isolation amount to a search when considered as a
group. The mosaic theory is therefore premised on aggregation:
it considers whether a set of nonsearches aggregated together
amount to a search because their collection and subsequent
analysis creates a revealing mosaic").
20
Court aggregates their sum total for its analysis." United
States v. Moore-Bush, 381 F. Supp. 3d 139, 149 (D. Mass. 2019).
As the analogy goes, the color of a single stone depicts little,
but by stepping back one can see a complete mosaic.
This aggregation principle or mosaic theory is wholly
consistent with the statement in Katz, 389 U.S. at 351, that
"[w]hat a person knowingly exposes to the public . . . is not a
subject of Fourth Amendment protection," because the whole of
one's movements, even if they are all individually public, are
not knowingly exposed in the aggregate. As the United States
Court of Appeals for the District of Columbia Circuit explained:
"the whole of a person's movements over the course of a
month is not actually exposed to the public because the
likelihood a stranger would observe all those movements is
not just remote, it is essentially nil. It is one thing
for a passerby to observe or even to follow someone during
a single journey as he goes to the market or returns home
from work. It is another thing entirely for that stranger
to pick up the scent again the next day and the day after
that, week in and week out, dogging his prey until he has
identified all the places, people, amusements, and chores
that make up that person's hitherto private routine."
Maynard, 615 F.3d at 560.
A detailed account of a person's movements, drawn from
electronic surveillance, encroaches upon a person's reasonable
expectation of privacy because the whole reveals far more than
the sum of the parts. "The difference is not one of degree but
of kind . . . ." Id. at 562. "Prolonged surveillance reveals
types of information not revealed by short-term surveillance,
21
such as what a person does repeatedly, what he does not do, and
what he does ensemble." Id. Aggregated location data reveals
"a highly detailed profile, not simply of where we go, but by
easy inference, of our associations -- political, religious,
amicable and amorous, to name only a few -- and of the pattern
of our professional and avocational pursuits." Commonwealth v.
Connolly, 454 Mass. 808, 834 (2009) (Gants, J., concurring),
quoting People v. Weaver, 12 N.Y.3d 433, 442 (2009).
iii. Constitutional implications of ALPRs. With this
theoretical foundation in mind, we turn to the central question
of this case: whether the use of ALPRs by the police invades an
objective, reasonable expectation of privacy. Or, more
specifically, we must determine whether ALPRs produce a detailed
enough picture of an individual's movements so as to infringe
upon a reasonable expectation that the Commonwealth will not
electronically monitor that person's comings and goings in
public over a sustained period of time. See, e.g., Augustine,
467 Mass. at 247-248.
A. ALPRs under the mosaic theory. In determining whether
a reasonable expectation of privacy has been invaded, it is not
the amount of data that the Commonwealth seeks to admit in
evidence that counts, but, rather, the amount of data that the
government collects or to which it gains access. See
Commonwealth v. Estabrook, 472 Mass. 852, 858-859 (2015), citing
22
Augustine, 467 Mass. at 254 ("in terms of reasonable expectation
of privacy, the salient consideration is the length of time for
which a person's CSLI is requested, not the time covered by the
person's CSLI that the Commonwealth ultimately seeks to use as
evidence at trial"). In Rousseau, 465 Mass. at 376, 382, we
weighed the thirty-one days of GPS monitoring in the
constitutional analysis, not the data that placed the vehicle
near the suspected arsons on four specific dates. Similarly, in
Carpenter, 138 S. Ct. at 2212-2213, the relevant period was the
127 days of CSLI data, not the data that placed the defendant
near the robberies on four particular days.11 For this reason,
our constitutional analysis ideally would consider every ALPR
11Our holding in Commonwealth v. Johnson, 481 Mass. 710,
722, cert. denied, 140 S. Ct. 247 (2019), is not to the
contrary. There, we determined that the imposition of GPS
monitoring on a specific probationer was a search, but a
reasonable one in the circumstances. Id. at 720. We then
concluded that the subsequent examination of the probationer's
location data by law enforcement was not a search, because the
probationer had no reasonable expectation of privacy in his
location; he knew he was wearing a GPS ankle monitor that was
transmitting his location to the government. See id. at 722-
725, 728. As an ancillary rationale, we emphasized that the
police only sought the defendant's location at the specific
times of various robberies, thus minimizing the intrusion. Id.
at 727-728. Throughout, we emphasized the importance of the
individual's status as a probationer, contrasting his
expectations of privacy with those of a nonprobationer. Id.
at 724 ("There is no question that the reasonableness of any
expectations of privacy held by a probationer knowingly subject
to GPS monitoring as a condition of probation is far different
from the reasonableness of the expectations of privacy held by
individuals who are surreptitiously tracked by law
enforcement").
23
record of a defendant's vehicle that had been stored and
collected by the government up to the time of the defendant's
arrest. That information, however, is not in the record before
us.
With enough cameras in enough locations, the historic
location data from an ALPR system in Massachusetts would invade
a reasonable expectation of privacy and would constitute a
search for constitutional purposes. The one-year retention
period indicated in the EOPSS retention policy certainly is long
enough to warrant constitutional protection. See Augustine, 467
Mass. at 254–255 ("tracking of the defendant's movements [by
CSLI] in the urban Boston area for two weeks was more than
sufficient to intrude upon the defendant's expectation of
privacy safeguarded by art. 14"); Rousseau, 465 Mass. at 382
(thirty-one days of GPS monitoring was sufficient duration to
conclude monitoring was search). Like CSLI data, ALPRs allow
the police to reconstruct people's past movements without
knowing in advance who police are looking for, thus granting
police access to "a category of information otherwise [and
previously] unknowable." See Carpenter, 138 S. Ct. at 2218.
Like both CSLI and GPS data, ALPRs circumvent traditional
constraints on police surveillance power by being cheap
(relative to human surveillance) and surreptitious.
24
Of course, the constitutional question is not merely an
exercise in counting cameras; the analysis should focus,
ultimately, on the extent to which a substantial picture of the
defendant's public movements are revealed by the surveillance.
For that purpose, where the ALPRs are placed matters too. ALPRs
near constitutionally sensitive locations -- the home, a place
of worship, etc. -- reveal more of an individual's life and
associations than does an ALPR trained on an interstate highway.
A network of ALPRs that surveils every residential side street
paints a much more nuanced and invasive picture of a driver's
life and public movements than one limited to major highways
that open into innumerable possible destinations. For while no
ALPR network is likely to be as detailed in its surveillance as
GPS or CSLI data, one well may be able to make many of the same
inferences from ALPR data that implicate expressive and
associative rights.12 See American Civ. Liberties Union Found.
of S. Cal. v. Superior Court of Los Angeles County, 3 Cal. 5th
12 The International Association of Chiefs of Police has
warned that collecting ALPR data from multiple sources creates
the risk "that individuals will become more cautious in the
exercise of their protected rights of expression, protest,
association, and political participation because they consider
themselves under constant surveillance." International
Association of Chiefs of Police, Privacy Impact Assessment
Report for the Utilization of License Plate Readers, at 13
(Sept. 2009), https://www.theiacp.org/sites/default/files/all
/k-m/LPR_Privacy_Impact_Assessment.pdf [https://perma.cc/M2T4
-G5F5].
25
1032, 1044 (2017) (ALPR data "could potentially reveal where [a]
person lives, works, or frequently visits").
Similarly, with cameras in enough locations, the hot list
feature could implicate constitutional search protections by
invading a reasonable expectation of privacy in one's real-time
location. If deployed widely enough, ALPRs could tell police
someone's precise, real-time location virtually any time the
person decided to drive, thus making ALPRs the vehicular
equivalent of a cellular telephone "ping." See Almonor, 482
Mass. at 55 (Lenk, J., concurring) ("When police act on real-
time information by arriving at a person's location, they signal
to both the individual and his or her associates that the person
is being watched. . . . To know that the government can find
you, anywhere, at any time is -- in a word -- 'creepy'"). Of
course, no matter how widely ALPRs are deployed, the exigency
exception to the warrant requirement would apply to this hot
list feature.13
13Order TRF-11 gives a nonexclusive list of reasons for
which authorized users may manually place a license plate on a
hot list, including "AMBER" alerts, missing child alerts,
missing college student bulletins, and "be on the look out"
alerts. In these circumstances, the use of real-time alerts may
be constitutionally permissible under the exigent circumstances
exception to the warrant requirement. See Riley v. California,
573 U.S. 373, 388, 391, 402 (2014) (repeatedly noting how
exigent circumstances exception might apply to warrant
requirement for cellular telephone searches); Warden, Md.
Penitentiary v. Hayden, 387 U.S. 294, 298–299 (1967) ("The
Fourth Amendment does not require police officers to delay in
26
Finally, like carrying a cellular telephone, driving is an
indispensable part of modern life, one we cannot and do not
expect residents to forgo in order to avoid government
surveillance.
B. Number and location of ALPR data collection points in
this case. On this record, however, we need not, and indeed
cannot, determine how pervasive a system of ALPRs would have to
be to invade a reasonable expectation of privacy. While a
testifying expert alluded to cameras "all over the [S]tate," the
record is silent as to how many of these cameras currently
exist,14 where they are located, and how many of them detected
the defendant.
Therefore, for this case, we consider the constitutional
import of four cameras placed at two fixed locations on the ends
of the Bourne and Sagamore bridges. "Fourth Amendment [and art.
14] cases must be decided on the facts of each case, not by
extravagant generalizations. '[W]e have never held that
the course of an investigation if to do so would gravely
endanger their lives or the lives of others"). Similarly, the
use of ALPRs to find a vehicle reported stolen would not be
constitutionally impermissible, because the driver of a stolen
vehicle does not have a reasonable expectation of privacy in the
location of someone else's automobile.
14The amici submit that, in 2015, there were 168 ALPR
cameras in operation in Massachusetts. The information provided
by the amici was not before the motion judge and remains
untested by the adversarial process.
27
potential, as opposed to actual, invasions of privacy constitute
searches for purposes of the Fourth Amendment.'" Dow Chem. Co.
v. United States, 476 U.S. 227, 238 n.5 (1986), quoting United
States v. Karo, 468 U.S. 705, 712 (1984).
"There is no real question that the government, without
securing a warrant, may use electronic devices to monitor an
individual's movements in public to the extent that the same
result could be achieved through visual surveillance."
Augustine, 467 Mass. at 252. It is an entirely ordinary
experience to drive past a police officer in a cruiser observing
traffic on the side of the road, and, of course, an officer may
read or write down a publicly displayed license plate number.
See Starr, 55 Mass. App. Ct. at 594. In this way, a single
license plate reader is similar to traditional surveillance
techniques. On the other hand, four factors distinguish ALPRs
from an officer parked on the side of the road: (1) the policy
of retaining the information for, at a minimum, one year;
(2) the ability to record the license plate number of nearly
every passing vehicle; (3) the continuous, twenty-four hour
nature of the surveillance; and (4) the fact that the recorded
license plate number is linked to the location of the
observation. These are enhancements of what reasonably might be
expected from the police.
28
The limited number of cameras and their specific
placements, however, also are relevant in determining whether
they reveal a mosaic of location information that is
sufficiently detailed to invade a reasonable expectation of
privacy. The cameras in question here gave police only the
ability to determine whether the defendant was passing onto or
off of the Cape at a particular moment, and when he had done so
previously. This limited surveillance does not allow the
Commonwealth to monitor the whole of the defendant's public
movements, or even his progress on a single journey. These
particular cameras make this case perhaps more analogous to
CSLI, if there were only two cellular telephone towers
collecting data. Such a limited picture does not divulge "the
whole of [the defendant's] physical movements," Carpenter, 138
S. Ct. at 2217, or track enough of his comings and goings so as
to reveal "the privacies of life." Id., quoting Riley, 573 U.S.
at 403. See Boyd v. United States, 116 U.S. 616, 630 (1886).
While we cannot say precisely how detailed a picture of the
defendant's movements must be revealed to invoke constitutional
protections, it is not that produced by four cameras at fixed
locations on the ends of two bridges.15 Therefore, we conclude
15In declining to establish a bright-line rule for when the
use of ALPRs constitutes a search, we recognize this may bring
some interim confusion. We trust, however, that as our cases
develop, this constitutional line gradually and appropriately
29
that the limited use of ALPRs in this case does not constitute a
search within the meaning of either art. 14 or the Fourth
Amendment.16
b. Defendant's other arguments. We turn to the
defendant's remaining claims. He argues that various evidence
should be suppressed because (1) the Barnstable police did not
show a written policy governing ALPR use, and the State police
ALPR policy, adopted by the Barnstable police, is deficient and
constitutionally inadequate; (2) the use of ALPR systems
violates 18 U.S.C. §§ 2701-2712, the Federal Stored
Communications Act (SCA), and 18 U.S.C. §§ 2510-2523, the
Federal Electronic Communications Privacy Act (ECPA); (3) the
court should adopt the doctrine of target standing; and (4) the
incriminating statements were involuntarily coerced through
will come into focus. "The judiciary risks error by elaborating
too fully on the Fourth Amendment [or art. 14] implications of
emerging technology before its role in society has become
clear." Ontario v. Quon, 560 U.S. 746, 759 (2010).
16The defendant argues that, if the ALPR data were
suppressed, there would have been no probable cause for his
arrest. Because we conclude that the use of the ALPR data was
not a search in the constitutional sense, the data gleaned from
the use of the ALPR properly is considered in the probable cause
analysis. We discern no error in the motion judge's
determination that there was probable cause to arrest the
defendant when the ALPR data is included in that analysis.
30
police trickery in violation of the defendant's Miranda rights.17
We conclude that each of these arguments is without merit.
i. Role of police policies. The defendant argues that,
because the Barnstable police did not introduce a written policy
governing police use of ALPR data, and because the State police
policy, Order TRF-11, is inadequately specific, the evidence
against him must be suppressed. In support of this argument,
the defendant relies on cases where we have required police to
introduce evidence of a written policy to justify warrantless
inventory searches or to demonstrate "that sobriety checkpoints
be governed by standard, neutral guidelines that clearly forbid
the arbitrary selection of vehicles to be initially stopped."
Commonwealth v. Murphy, 454 Mass. 318, 323 (2009) (sobriety
checkpoint guidelines). See Commonwealth v. Bishop, 402 Mass.
449, 451 (1988) ("art. 14 . . . requires the exclusion of
evidence seized during an inventory search not conducted
pursuant to standard police procedures, which procedures, from
now on, must be in writing").
17In addition to the arguments discussed here, the
defendant contends that the seizure of his bail money was
unlawful. The seizure of the defendant's bail money was not
part of the judge's decision on the motion to suppress and
therefore is not properly before this court. See Mass. R. Crim.
P. 15 (a) (2), as appearing in 474 Mass. 1501 (2016).
Accordingly, we do not consider it.
31
This argument is unavailing. These cases involve the
reasonableness of a search or seizure conducted under specific
exceptions to the warrant requirement, not the threshold
constitutional question whether a search or seizure has occurred
at all. Detailed policy guidelines for police use of ALPRs well
may be a "good idea," Riley, 573 U.S. at 398, but their
existence or lack thereof does not determine the constitutional
question.
ii. Statutory claims. The defendant argues further that
the government's use of ALPR data is subject to the SCA and the
ECPA. Neither statute, however, is applicable.18 The SCA
prevents the government from compelling a "provider of
electronic communication service" to produce such communications
without following certain procedures. See 18 U.S.C. § 2703.
Here, the government did not compel production of electronic
communications, but, rather, created and used them in the first
instance. Similarly, the ECPA regulates the interception of
18The defendant's reliance on G. L. c. 214, § 1B, is
similarly misplaced. That statute creates a cause of action for
tort liability to "protect[] individuals from 'disclosure of
facts . . . that are of a highly personal or intimate nature
when there exists no legitimate, countervailing interest.'" Doe
v. Brandeis Univ., 177 F. Supp. 3d 561, 616 (D. Mass. 2016),
quoting Dasey v. Anderson, 304 F.3d 148, 153–154 (1st Cir.
2002). While it conceivably could support tort litigation
against government actors (subject, of course, to sovereign
immunity constraints), it has no application to the criminal
suppression context.
32
wire, oral, and electronic communications. See 18 U.S.C.
§ 2511. As the motion judge correctly determined, it would
produce an absurd reading of the statute to conclude that
officers were intercepting their own communications when
receiving real-time alerts. See 18 U.S.C. § 2511(2)(c) ("It
shall not be unlawful under this chapter for a person acting
under color of law to intercept a wire, oral, or electronic
communication, where such person is a party to the communication
. . ."). See also 18 U.S.C. § 2510(5)(a) (exempting any
telephone or equipment used by law enforcement officers in
course of their duties from types of devices that can be used to
"intercept").
iii. Target standing. The defendant also argues that this
court should adopt the doctrine of "target standing," which
would give him standing to contest the search of his codefendant
because he was one of that search's secondary targets. See
Commonwealth v. Santiago, 470 Mass. 574, 577 (2015). It would
allow him "to assert that a violation of the Fourth Amendment
rights of a third party entitled him to have evidence suppressed
at his trial." Id. The United States Supreme Court has
rejected the doctrine with respect to the Fourth Amendment.
Rakas v. Illinois, 439 U.S. 128, 132-133 (1978). We also
repeatedly have declined to adopt target standing under art. 14,
but have left open the possibility of applying the doctrine in
33
cases of "distinctly egregious police conduct." See Santiago,
supra at 577-578. Nothing in this record suggests "distinctly
egregious police conduct." Therefore, the defendant does not
have target standing to challenge evidence seized from his
codefendant.
iv. Miranda waiver. The defendant argues that his waiver
of his Miranda rights and the statements he made to police were
involuntary because the officers repeatedly told him that he was
not under arrest. The tests to determine whether a Miranda
waiver was voluntary and for the voluntariness of a statement
are "essentially the same" (citation omitted). Commonwealth v.
Newson, 471 Mass. 222, 229 (2015).
With respect to the Miranda issue, the motion judge found
the following. First, the defendant was under arrest at the
time he was handcuffed during the roadside stop. He properly
and carefully was advised of his Miranda rights immediately
after being handcuffed, and again at the police station. He
understood these rights both times.
We agree with the motion judge that questions asked at the
roadside and at the police station constituted custodial
interrogation. Considering the totality of the circumstances,
the only factor indicating a lack of voluntariness was the
officers' statements that the defendant was not under arrest and
that he might avoid arrest by giving the information he
34
initially promised. The defendant argues that the waiver and
the statements were involuntary based on these deceptive
representations.
"[D]eception or trickery does not necessarily compel
suppression of the confession or admission but, instead, is one
factor to be considered in a totality of the circumstances
analysis." Newson, 471 Mass. at 230, quoting Commonwealth v.
Tremblay, 460 Mass. 199, 208 (2011). In Newson, supra, this
court held that even if an officer engaged in deceit or trickery
by telling a defendant that he was not under arrest, such deceit
would not be enough to demonstrate involuntariness. Here, the
facts are essentially the same. Therefore, we do not disturb
the judge's finding that the Commonwealth proved beyond a
reasonable doubt that the statements and the Miranda waiver were
voluntary.
3. Conclusion. While we recognize that the widespread use
of ALPRs in the Commonwealth could implicate constitutional
protections against unreasonable searches, the limited use of
the technology in this case does not.
Order denying motions to
suppress affirmed.
GANTS, C.J. (concurring). I agree with the court that, if
the State police had obtained historical locational data
regarding the defendant's vehicle from enough automatic license
plate readers (ALRPs) in enough locations, the mosaic that such
collection would create of the defendant's movements "would
invade a reasonable expectation of privacy and would constitute
a search for constitutional purposes." Ante at . I also
agree with the court that the locational information regarding
the defendant that was obtained from four ALPRs at two fixed
locations on two bridges falls short of creating the type of
mosaic that would constitute a search within the meaning of
either art. 14 of the Massachusetts Declaration of Rights or the
Fourth Amendment to the United States Constitution. And I agree
that the court is correct to forbear from declaring in this case
"precisely how detailed a picture of the defendant's movements
must be revealed to invoke constitutional protections." Id.
at . I write separately not to attempt to answer how
detailed the picture must be but to suggest an analytical
framework that might prove useful in future cases.
It is important to recognize that this is the first case we
have encountered where the State police are collecting and
storing a vast amount of locational data, from which they
potentially might conduct a targeted search of locational
information for a particular person or vehicle without probable
2
cause and without court authorization. Cellular telephone
companies possess even more locational data that can track the
movements of a cellular telephone (and thus the person in
possession of it), but law enforcement may obtain that
information from these companies only through a search warrant
or court order.
Under our case law, a search warrant based on probable
cause is required for law enforcement to obtain more than six
hours of historical telephone call cellular site location
information (CSLI) regarding a particular individual. See
Commonwealth v. Estabrook, 472 Mass. 852, 854 (2015);
Commonwealth v. Augustine, 467 Mass. 230, 255 (2014), S.C., 470
Mass. 837 (2015). A court order under 18 U.S.C. § 2703 based on
"specific and articulable facts" that show "reasonable grounds
to believe" that the records "are relevant and material to an
ongoing criminal investigation" suffices under art. 14 to obtain
six hours or less of CSLI regarding a particular individual.
See Estabrook, supra at 855 n.4, 858. If a law enforcement
agency possessed comparable historical locational data that
could produce a mosaic of an individual's movements equivalent
to that produced by CSLI, whether because it purchased bulk CSLI
data from a vendor or because it had a vast array of ALPRs or
surveillance cameras using facial recognition software, we would
require law enforcement to obtain a search warrant based on
3
probable cause before it could retrieve the locational data for
that mosaic regarding a targeted individual.
But what if the historical locational information regarding
a targeted individual that can be obtained from data in the
possession of a law enforcement agency could yield a mosaic of
location points that is less than that created by CSLI but
greater than the four location points established in this
record? Pragmatically, I submit we have two alternatives. Our
first option is to determine based on the facts of a particular
case when the locational mosaic of a targeted individual's
movements crosses the threshold of the reasonable expectation of
privacy. A mosaic above that threshold would require a search
warrant based on probable cause, but a mosaic below that
threshold would not require any court authorization.
Alternatively, we could strike a balance analogous to that
struck by the United States Supreme Court in Terry v. Ohio, 392
U.S. 1, 21 (1968), and decide that there are two locational
mosaic thresholds: a lesser threshold that may be permissibly
crossed with a court order supported by an affidavit showing
reasonable suspicion and a greater threshold that is permissibly
crossed only with a search warrant supported by probable cause.
The reasonable suspicion standard would require "specific and
articulable facts" demonstrating reasonable suspicion that the
targeted individual has committed, is committing, or will commit
4
a crime, see id. at 21-22, and that there are reasonable grounds
to believe that the data obtained from the query are relevant
and material to an investigation of the crime. The reasonable
suspicion standard is different from and more exacting than the
standard required under 18 U.S.C. § 2703 to obtain six hours or
less of CSLI, which requires only "specific and articulable
facts" that show "reasonable grounds to believe" that the
records "are relevant and material to an ongoing criminal
investigation."
This second alternative would mean that law enforcement
agencies would need to obtain court authorization more often
before retrieving targeted individual historical locational
information in their possession because queries that would not
require a showing of probable cause might still require a
showing of reasonable suspicion. But the benefit to law
enforcement would be that, if the police sought a court order
based on reasonable suspicion and a reviewing court determined
that the query sought locational data that could yield a mosaic
of movement requiring a showing of probable cause, the search
would not be found unconstitutional (and the information
collected would not be suppressed) if the reviewing court found
that the affidavit supported a finding of probable cause. In
contrast, where no court order was obtained and a reviewing
court determined that probable cause or reasonable suspicion was
5
required to support the retrieval of historical locational
information, the data retrieved from the query would have to be
suppressed even if law enforcement could have met the applicable
standard.
Regardless of which alternative the court ultimately
chooses, a reviewing court will need to know the extent of the
mosaic that was possible from the retrieval of historical
locational information regarding the movements of a targeted
individual, because only then can the court accurately determine
whether the threshold had been crossed. Therefore, unless the
law enforcement agency has sought prior court approval to search
for particularized locational data in its possession, the agency
will have to preserve each and every search query for the
retrieval of historical locational information regarding a
targeted individual. For instance, if the State police maintain
1,000 ALPRs at different locations throughout the Commonwealth,
it matters whether they searched for a suspect's vehicle from
the data yielded by all 1,000 cameras or only by four cameras,
and it matters whether they gathered this data for one day or
one hundred days. And regardless of whether a court authorized
the search, the agency must preserve the historical locational
data regarding a particular individual that the agency retrieved
as a result of such queries from the data in its possession,
even when that exceeds the amount of data that the agency uses
6
in an investigation or at trial. Cf. Estabrook, 472 Mass. at
859 ("the salient consideration is the length of time for which
a person's CSLI is requested, not the time covered by the
person's CSLI that the Commonwealth ultimately seeks to use as
evidence at trial"). And the agency must make this preserved
data and search request available in discovery when sought by
the defendant. Only then will a court have the information it
needs to determine whether the retrieval of locational
information regarding a targeted individual crossed a
constitutional threshold that requires court authorization and
either reasonable suspicion or probable cause.