(Slip Opinion) OCTOBER TERM, 2021 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
SHOOP, WARDEN v. TWYFORD
CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
THE SIXTH CIRCUIT
No. 21–511. Argued April 26, 2022—Decided June 21, 2022
Respondent Raymond Twyford was convicted by an Ohio jury of aggra-
vated murder and other charges and was sentenced to death. The Ohio
appellate courts affirmed his conviction and sentence. Twyford then
sought state postconviction relief, claiming that his trial counsel was
ineffective for failing to present evidence of a head injury Twyford sus-
tained as a teenager. The Ohio courts rejected his claim, concluding
that trial counsel had simply presented a competing psychological the-
ory for Twyford’s actions. Twyford then filed a petition for federal ha-
beas relief. The District Court dismissed most of Twyford’s claims as
procedurally defaulted but allowed a few to proceed. He then moved
for an order compelling the State to transport him to a medical facility,
arguing that neurological testing would plausibly lead to the develop-
ment of evidence to support his claim that he suffers neurological de-
fects. The District Court granted Twyford’s motion under the All Writs
Act, which authorizes federal courts to “issue all writs necessary or
appropriate in aid of their respective jurisdictions and agreeable to the
usages and principles of law.” 28 U. S. C. §1651(a). The Court of Ap-
peals affirmed. Both courts concluded that it was unnecessary to con-
sider the admissibility of any resulting evidence prior to ordering the
State to transport Twyford to gather it.
Held: A transportation order that allows a prisoner to search for new ev-
idence is not “necessary or appropriate in aid of” a federal court’s ad-
judication of a habeas corpus action when the prisoner has not shown
that the desired evidence would be admissible in connection with a
particular claim for relief. Pp. 4–11.
(a) The State argues that the All Writs Act does not authorize the
issuance of transportation orders for medical testing at all. The State
also argues that the order issued in this case was not “necessary or
2 SHOOP v. TWYFORD
Syllabus
appropriate in aid of” the District Court’s jurisdiction because Twyford
failed to show that the evidence he hoped to find would be useful to his
habeas case. Because this Court agrees with the State’s second argu-
ment, it does not address the first.
In habeas cases such as this, the Antiterrorism and Effective Death
Penalty Act (AEDPA) restricts a federal court’s authority to grant re-
lief. AEDPA provides that a federal habeas court cannot grant relief
in a case adjudicated on the merits in state court unless the state court
(1) contradicted or unreasonably applied this Court’s precedents, or (2)
handed down a decision “based on an unreasonable determination of
the facts in light of the evidence presented in the State court proceed-
ing.” §§2254(d)(1)–(2). AEDPA also restricts the ability of a federal
habeas court to develop and consider new evidence, limiting review of
factual determinations under §2254(d)(2) to “the evidence presented in
the State court proceeding,” and review of legal claims under
§2254(d)(1) “to the record that was before the state court.” Cullen v.
Pinholster, 563 U. S. 170, 181. A federal court may admit new evi-
dence only in two limited situations: Either the claim must rely on a
“new” and “previously unavailable” “rule of constitutional law” made
retroactively applicable by this Court, or it must rely on “a factual
predicate that could not have been previously discovered through the
exercise of due diligence.” §2254(e)(2)(A). But before a federal court
may decide whether to grant an evidentiary hearing or “otherwise con-
sider new evidence” under §2254(e)(2), it must first determine that
such evidence could be legally considered in the prisoner’s case. Shinn
v. Martinez Ramirez, 596 U. S. ___, ___. That is because a federal court
“may never needlessly prolong a habeas case, particularly given the
essential need to promote the finality of state convictions.” Id., at ___
(internal quotation marks omitted).
Twyford’s transportation request was granted under the All Writs
Act. This Court has held that the All Writs Act cannot be used to cir-
cumvent statutory requirements or otherwise binding procedural
rules. See Pennsylvania Bureau of Correction v. United States Mar-
shals Service, 474 U. S. 34, 43. In federal habeas proceedings, AEDPA
provides the governing rules. And this Court’s precedents explain that
a district court must consider AEDPA’s requirements before facilitat-
ing the development of new evidence. By the same token, if an order
issued under the All Writs Act enables a prisoner to fish for unusable
evidence, such a writ would not be “necessary or appropriate in aid of”
the federal court’s jurisdiction, as all orders issued under the Act must
be. §1651(a). “[G]uided by the general principles underlying [this
Court’s] habeas corpus jurisprudence,” Calderon v. Thompson, 523
U. S. 538, 554, a writ that enables a prisoner to gather evidence that
would not be admissible would “needlessly prolong” resolution of the
Cite as: 596 U. S. ____ (2022) 3
Syllabus
federal habeas case, Shinn, 596 U. S., at ___, and frustrate the “State’s
interest[ ] in finality,” Calderon, 523 U. S., at 556. A federal court or-
der requiring a State to transport a prisoner to a public setting not
only delays resolution of his habeas case, but may also present serious
risks to public safety. Commanding a State to take such risks so that
a prisoner can search for unusable evidence would not be a “necessary
or appropriate” means of aiding a federal court’s limited habeas re-
view. Pp. 4–9.
(b) The District Court and Court of Appeals in this case concluded
that directing the State to transport Twyford to a medical facility
would aid the adjudication of his habeas petition, but they never de-
termined how this could aid his cause. For the reasons discussed, that
was error. Applying the proper standard here is straightforward.
Twyford never explained how the results of the neurological testing
could be admissible in his habeas proceedings, and it is hard to see
how they could be, since the District Court’s AEDPA review is limited
to “the record that was before the state court,” Pinholster, 563 U. S., at
181, and Twyford made no attempt to explain how that bar would be
inapplicable in his case. Twyford suggested that the results of his
brain testing could “plausibly” bear on the question whether to excuse
procedural default, but he did not identify the particular defaulted
claims nor explain how the testing would allow him to resurrect those
claims. Pp. 9–11.
11 F. 4th 518, reversed and remanded.
ROBERTS, C. J., delivered the opinion of the Court, in which THOMAS,
ALITO, KAVANAUGH, and BARRETT, JJ., joined. BREYER, J., filed a dissent-
ing opinion, in which SOTOMAYOR and KAGAN, JJ., joined. GORSUCH, J.,
filed a dissenting opinion.
Cite as: 596 U. S. ____ (2022) 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. 21–511
_________________
TIM SHOOP, WARDEN, PETITIONER v.
RAYMOND A. TWYFORD, III
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE SIXTH CIRCUIT
[June 21, 2022]
CHIEF JUSTICE ROBERTS delivered the opinion of the
Court.
The All Writs Act authorizes federal courts to “issue all
writs necessary or appropriate in aid of their respective ju-
risdictions and agreeable to the usages and principles of
law.” 28 U. S. C. §1651(a). In this case, the District Court
ordered the State to transport a prisoner in its custody to a
hospital for medical testing. The prisoner argued that the
testing could reveal evidence helpful in his effort to obtain
habeas corpus relief. The question is whether the District
Court’s order is “necessary or appropriate in aid of ” the fed-
eral court’s resolution of the prisoner’s habeas case. We
hold that it is not, and therefore reverse.
I
On the evening of September 23, 1992, Raymond Twyford
and his co-conspirator lured Richard Franks to a remote lo-
cation, and shot and killed him. To hide their crime, the
pair mutilated Franks’s body and pushed it into a pond.
But a sheriff found the body a few days later, and his inves-
tigation led to Twyford. Twyford confessed, claiming that
Franks had raped his girlfriend’s daughter and that he had
2 SHOOP v. TWYFORD
Opinion of the Court
killed Franks out of revenge. A jury convicted Twyford of
aggravated murder, kidnapping, robbery, and other
charges, and he was sentenced to death. The Ohio appel-
late courts affirmed his conviction and sentence, State v.
Twyford, 94 Ohio St. 3d 340, 763 N. E. 2d 122, and this
Court denied certiorari, 537 U. S. 917 (2002).
Twyford then sought postconviction relief in Ohio state
court. Relevant here, he claimed that his trial counsel was
ineffective for failing to present evidence of a head injury
Twyford sustained as a teenager during a suicide attempt.
That injury, Twyford argued, left him “unable to make ra-
tional and voluntary choices.” State v. Twyford, 2001 WL
301411, *10 (Ohio App. 7th, Mar. 19, 2001). The Ohio trial
court and Court of Appeals rejected this claim on the mer-
its, concluding that “a finding of ineffective assistance can-
not be based upon the trial counsel’s choice of one compet-
ing psychological explanation over another.” Id., at *13.
The Court of Appeals noted that Twyford’s counsel had
called a psychologist who testified in support of a com-
pletely different theory: that Twyford’s “commission of the
murder was his way of protecting the alleged rape victim
from the same type of abusive behavior [he] had experi-
enced when he was young.” Ibid. Unlike the head injury
theory, this one explained Twyford’s seemingly deliberate
and rational actions: planning a fake hunting trip as a ruse
to lure Franks to a remote location, dismembering his body,
and disposing of it in such a way as would conceal his iden-
tity. This theory was also consistent with Twyford’s own
written confession, which described his plan in detail. The
Ohio Supreme Court denied review. State v. Twyford, 95
Ohio St. 3d 1436, 2002-Ohio-2084, 766 N. E. 2d 1002 (Ta-
ble).
In 2003, Twyford filed a petition in federal court for ha-
beas relief, from which this case stems. Despite the passing
of two decades, relatively little has happened. The State
moved in 2008 to dismiss many of Twyford’s claims on the
Cite as: 596 U. S. ____ (2022) 3
Opinion of the Court
ground that he failed to raise them in state court. The
District Court did not rule on that motion for nine years.
Eventually, it dismissed most of Twyford’s claims as proce-
durally defaulted but allowed a few, including some ineffec-
tive assistance of counsel claims, to proceed. Twyford v.
Bradshaw, No. 2:03–cv–906 (SD Ohio, Sept. 27, 2017).
Twyford then moved for an order compelling the State “to
transport [him] to The Ohio State University Medical Cen-
ter for medical testing necessary for the investigation,
presentation, and development of claims.” Motion to
Transport for Medical Testing in No. 2:03–cv–906 (SD
Ohio), p. 1 (Motion to Transport). Twyford explained that
such testing could not be conducted at the prison, and ar-
gued that it was necessary to determine whether he suffers
neurological defects due to childhood physical abuse, alco-
hol and drug use, and the self-inflicted gunshot wound to
his head. Id., at 3. In support of his motion, he attached a
letter from a neurologist stating that “a CT/FDG-PET scan
would be a useful next step to further evaluate [him] for
brain injury,” in part because previous scans revealed 20 to
30 metal fragments in his skull. App. to Pet. for Cert. 272a.
Twyford argued that it was “plausible” that the testing was
“likely to reveal evidence in support of ” claims and that it
“could plausibly lead to the development of evidence and
materials” that could counter arguments of “procedural de-
fault or exhaustion.” Motion to Transport 8. He also urged
the court to disregard, at least for now, the question
whether the results of the brain testing would be admissi-
ble.
The District Court granted Twyford’s motion and ordered
the State to transport him to the Medical Center. It deter-
mined that the order was appropriate under the All Writs
Act, which authorizes federal courts to “issue all writs nec-
essary or appropriate in aid of their respective jurisdictions
and agreeable to the usages and principles of law.” 28
U. S. C. §1651(a). The District Court did not address
4 SHOOP v. TWYFORD
Opinion of the Court
whether it would be able to consider the evidence that
Twyford hoped to develop.
The District Court stayed the transportation order pend-
ing appeal, and the Court of Appeals affirmed, 11 F. 4th 518
(CA6 2021). That court first concluded that transportation
orders to gather evidence are “agreeable to the usages and
principles of law.” §1651(a). It then determined that
Twyford’s transportation to gather evidence was “necessary
or appropriate” under the Act because the desired evidence
“plausibly relate[d]” to his claims for relief. 11 F. 4th, at
526–527. Like the District Court, the Court of Appeals con-
cluded that it was not required to “consider the admissibil-
ity of any resulting evidence” before ordering the State to
transport Twyford to gather it. Id., at 527.
Judge Batchelder dissented, contending that such an or-
der is “necessary or appropriate in aid of ” a court’s jurisdic-
tion only if “(1) the petitioner has identified specific claims
for relief that the evidence being sought would support or
further; and (2) the district court has determined that if
that evidence is as the petitioner proposed or anticipated,
then it could entitle the petitioner to habeas relief.” Id., at
529. The majority’s approach, she argued, allowed Twyford
to “proceed in reverse order by collecting evidence before
justifying it.” Ibid.
We granted certiorari. 595 U. S. ___ (2022).
II
The State argues that the lower courts erred for two in-
dependent reasons. First, the State contends that the All
Writs Act does not authorize the issuance of transportation
orders for medical testing at all. Second, the State argues
that the transportation order was not “necessary or appro-
priate in aid of” the District Court’s jurisdiction because
Twyford failed to show that the evidence he hoped to find
would be useful to his habeas case. We agree with the
State’s second argument and thus need not address the
Cite as: 596 U. S. ____ (2022) 5
Opinion of the Court
first.1
A
A federal court’s power to grant habeas relief is restricted
under the Antiterrorism and Effective Death Penalty Act of
1996 (AEDPA), which provides that the writ may issue
“only on the ground that [the prisoner] is in custody in vio-
lation of the Constitution or laws or treaties of the United
States.” 28 U. S. C. §2254(a). To understand the propriety
of the transportation order the District Court entered while
adjudicating Twyford’s habeas corpus action, it is necessary
to review the limits AEDPA imposes on federal courts.
Congress enacted AEDPA “to reduce delays in the execu-
tion of state and federal criminal sentences, particularly in
capital cases,” Woodford v. Garceau, 538 U. S. 202, 206
(2003), and to advance “the principles of comity, finality,
——————
1 The Court of Appeals concluded that it had jurisdiction to review the
District Court’s order, and we agree. See Cohen v. Beneficial Industrial
Loan Corp., 337 U. S. 541, 546 (1949). Transportation orders issued un-
der the All Writs Act (1) conclusively require transportation; (2) resolve
an important question of state sovereignty conceptually distinct from the
merits of the prisoner’s claims, see Puerto Rico Aqueduct and Sewer Au-
thority v. Metcalf & Eddy, Inc., 506 U. S. 139, 144–145 (1993); and (3) are
entirely unreviewable by the time the case has gone to final judgment.
The dissent treats the order at issue as a mere discovery order, see post,
at 3–7 (opinion of BREYER, J.), but that glosses over what it entails: re-
quiring a State to take a convicted felon outside the prison’s walls. Such
an order creates public safety risks and burdens on the State that cannot
be remedied after final judgment, and we have in fact reviewed an iden-
tical order before. See Pennsylvania Bureau of Correction v. United
States Marshals Service, 474 U. S. 34 (1985); see also Brief for Petition-
ers 10, n. 6, and Brief for Federal Respondents 17, n. 8, in Pennsylvania
Bureau of Correction, O. T. 1984, No. 84–489 (noting the Cohen jurisdic-
tional issue). Every Court of Appeals to consider the question, moreover,
has held that such orders are immediately appealable. See 11 F. 4th 515,
522 (CA6 2021); Jones v. Lilly, 37 F. 3d 964, 965–966 (CA3 1994); Jack-
son v. Vasquez, 1 F. 3d 885, 887–888 (CA9 1993); Ballard v. Spradley,
557 F. 2d 476, 479 (CA5 1977); see also Barnes v. Black, 544 F. 3d 807,
810–811 (CA7 2008).
6 SHOOP v. TWYFORD
Opinion of the Court
and federalism,” Williams v. Taylor, 529 U. S. 420, 436
(2000) (Michael Williams). It furthered those goals “in
large measure [by] revising the standards used for evaluat-
ing the merits of a habeas application.” Garceau, 538 U. S.,
at 206. Pertinent here, §2254(d) provides that if a claim
was adjudicated on the merits in state court, a federal court
cannot grant relief unless the state court (1) contradicted or
unreasonably applied this Court’s precedents, or (2) handed
down a decision “based on an unreasonable determination
of the facts in light of the evidence presented in the State
court proceeding.” The question under AEDPA is thus not
whether a federal court believes the state court’s determi-
nation was incorrect, but whether that determination was
unreasonable—“a substantially higher threshold” for a
prisoner to meet. Schriro v. Landrigan, 550 U. S. 465, 473
(2007); see also Harrington v. Richter, 562 U. S. 86, 102–
103 (2011).
AEDPA also restricts the ability of a federal habeas court
to develop and consider new evidence. Review of factual
determinations under §2254(d)(2) is expressly limited to
“the evidence presented in the State court proceeding.” And
in Cullen v. Pinholster, 563 U. S. 170 (2011), we explained
that review of legal claims under §2254(d)(1) is also “limited
to the record that was before the state court.” Id., at 181.
This ensures that the “state trial on the merits” is the “main
event, so to speak, rather than a tryout on the road for what
will later be the determinative federal habeas hearing.”
Wainwright v. Sykes, 433 U. S. 72, 90 (1977) (internal quo-
tation marks omitted).
If a prisoner “failed to develop the factual basis of a claim
in State court proceedings,” a federal court may admit new
evidence, but only in two quite limited situations.
§2254(e)(2). Either the claim must rely on a “new” and “pre-
viously unavailable” “rule of constitutional law” made ret-
roactively applicable by this Court, or it must rely on “a fac-
tual predicate that could not have been previously
Cite as: 596 U. S. ____ (2022) 7
Opinion of the Court
discovered through the exercise of due diligence.”
§2254(e)(2)(A). And even if a prisoner can satisfy one of
those two exceptions, he must also show that the desired
evidence would demonstrate, “by clear and convincing evi-
dence,” that “no reasonable factfinder” would have con-
victed him of the charged crime. §2254(e)(2)(B). Thus, alt-
hough state prisoners may occasionally submit new
evidence in federal court, “AEDPA’s statutory scheme is de-
signed to strongly discourage them from doing so.” Pinhol-
ster, 563 U. S., at 186; see also Michael Williams, 529 U. S.,
at 437 (“Federal courts sitting in habeas are not an alterna-
tive forum for trying facts and issues which a prisoner made
insufficient effort to pursue in state proceedings.”).
We have explained that a federal court, in deciding
whether to grant an evidentiary hearing or “otherwise con-
sider new evidence” under §2254(e)(2), must first take into
account these restrictions. Shinn v. Martinez Ramirez, 596
U. S. ___, ___ (2022) (slip op., at 21); see also Schriro, 550
U. S., at 474. The reasons for this are familiar. A federal
court “may never needlessly prolong a habeas case, particu-
larly given the essential need to promote the finality of
state convictions,” so a court must, before facilitating the
development of new evidence, determine that it could be le-
gally considered in the prisoner’s case. Shinn, 596 U. S., at
___ (slip op., at 21) (internal quotation marks and citation
omitted); see also Bracy v. Gramley, 520 U. S. 899, 904
(1997) (“A habeas petitioner, unlike the usual civil litigant
in federal court, is not entitled to discovery as a matter of
ordinary course.”). If §2254(e)(2) applies and the prisoner
cannot satisfy its “stringent requirements,” Michael Wil-
liams, 529 U. S., at 433, holding an evidentiary hearing or
otherwise expanding the state-court record would “prolong
federal habeas proceedings with no purpose,” Shinn, 596
U. S., at ___ (slip op., at 21) (internal quotation marks omit-
ted). And that would in turn disturb the “State’s significant
interest in repose for concluded litigation.” Harrington, 562
8 SHOOP v. TWYFORD
Opinion of the Court
U. S., at 103. A court therefore must, consistent with
AEDPA, determine at the outset whether the new evidence
sought could be lawfully considered.
This is true even when the All Writs Act is the asserted
vehicle for gathering new evidence. We have made clear
that a petitioner cannot use that Act to circumvent statu-
tory requirements or otherwise binding procedural rules.
See Pennsylvania Bureau of Correction v. United States
Marshals Service, 474 U. S. 34, 43 (1985) (“Although [the
Act] empowers federal courts to fashion extraordinary rem-
edies when the need arises, it does not authorize them to
issue ad hoc writs whenever compliance with statutory pro-
cedures appears inconvenient or less appropriate.”); Syn-
genta Crop Protection, Inc. v. Henson, 537 U. S. 28, 32–33
(2002) (same). AEDPA provides the governing rules for fed-
eral habeas proceedings, and our precedents explain that a
district court must consider that statute’s requirements be-
fore facilitating the development of new evidence. See
Schriro, 550 U. S., at 474; see also Shinn, 596 U. S., at ___
(slip op., at 21).
By the same token, a writ seeking new evidence would
not be “necessary or appropriate in aid of ” a federal habeas
court’s jurisdiction, as all orders issued under the All Writs
Act must be, if it enables a prisoner to fish for unusable ev-
idence, in the hope that it might undermine his conviction
in some way. In every habeas case, “the court must be
guided by the general principles underlying our habeas cor-
pus jurisprudence.” Calderon v. Thompson, 523 U. S. 538,
554 (1998). A writ that enables a prisoner to gather evi-
dence that would not be admissible would “needlessly pro-
long” resolution of the federal habeas case, Shinn, 596
U. S., at ___ (slip op., at 21), and frustrate the “State’s in-
terest[ ] in finality,” Calderon, 523 U. S., at 556. Cf. Harris
v. Nelson, 394 U. S. 286, 300 (1969) (recognizing, before
AEDPA, that a writ is “necessary or appropriate in aid of ”
a federal habeas court’s jurisdiction if “specific allegations”
Cite as: 596 U. S. ____ (2022) 9
Opinion of the Court
show that the petitioner may, “if the facts are fully devel-
oped,” be able to demonstrate that he is “entitled to relief ”).
A federal court order requiring a State to transport a pris-
oner to a public setting—here, a medical center for test-
ing—not only delays resolution of his habeas case, but may
also present serious risks to public safety. See Brief for
State of Utah et al. as Amici Curiae 7–18 (describing the
dangers inherent in prisoner transport); cf. Price v. John-
ston, 334 U. S. 266, 285 (1948) (a court should not require
that a prisoner be transported if doing so would cause “un-
due inconvenience or danger”).2 Commanding a State to
take these risks so that a prisoner can search for unusable
evidence would not be a “necessary or appropriate” means
of aiding a federal court’s limited habeas review.
B
The District Court entered an order directing the State to
transport Twyford to a medical facility, concluding that do-
ing so would aid its adjudication of his habeas petition. But
the court never determined how, in light of the limitations
on its review described above, newly developed evidence
could aid Twyford’s cause. See Twyford v. Warden, 2020
WL 1308318, *4 (SD Ohio, Mar. 19, 2020) (“the Court does
not find itself in a position at this stage of proceedings to
make a determination as to whether or to what extent it
would be precluded by Cullen v. Pinholster from considering
any new evidence”). Nor did the Sixth Circuit. See 11 F.
4th, at 527 (“At this stage, on review of Twyford’s interloc-
utory appeal seeking a transport order, we need not con-
sider the admissibility of any resulting evidence.”). For the
——————
2 These risks are not speculative. To give just one example, earlier this
year a convicted murderer escaped from a prison bus transporting him
to a medical appointment by breaking out of his restraints and stabbing
the bus driver. He was on the run for three weeks—and allegedly killed
a family of five during that time—before dying in a shootout with the
police. See M. Ives & A. Traub, Hunt for Escaped Murderer Ends in
Shootout With Police in Texas, N. Y. Times, June 4, 2022, p. A14.
10 SHOOP v. TWYFORD
Opinion of the Court
reasons just discussed, that was error.
Reviewing Twyford’s request for transportation under
the proper standard is straightforward, because his motion
sheds no light on how he might persuade a court to consider
the results of his testing, given the limitations AEDPA im-
poses on presenting new evidence. He argued that it is
“plausible that the testing to be administered is likely to
reveal evidence in support of ” his claims of ineffective as-
sistance of counsel and expert witness, lack of competency
to stand trial, and the involuntariness of his confession.
Motion to Transport 8. Whether or not that is true, Twyford
never explained how the results of the neurological testing
could be admissible in his habeas proceeding, and it is hard
to see how they could be. The Ohio courts already adjudi-
cated and rejected most of these claims on the merits, and
the District Court’s AEDPA review will therefore be limited
to “the record that was before the state court.” Pinholster,
563 U. S., at 181. As for the claims that the state courts did
not consider, Twyford never argued that he could clear the
bar in §2254(e)(2) for expanding the state court record, or
that the bar was somehow inapplicable.
Twyford asserted in passing that the desired evidence
could “plausibly” bear on the question whether to excuse
procedural default. Motion to Transport 8. By way of back-
ground, a federal court may not review a claim a habeas
petitioner failed to adequately present to state courts, un-
less he shows “cause to excuse his failure to comply with the
state procedural rule and actual prejudice resulting from
the alleged constitutional violation.” Davila v. Davis, 582
U. S. ___, ___ (2017) (slip op., at 5) (internal quotation
marks omitted). Twyford suggested that the results of his
brain testing could help make that showing. But he did not
identify the particular defaulted claims he hopes to resur-
rect, nor did he explain how the testing would matter to his
ability to do so. And in any event, this Court has already
held that, if §2254(e)(2) applies and the prisoner cannot
Cite as: 596 U. S. ____ (2022) 11
Opinion of the Court
meet the statute’s standards for admitting new merits evi-
dence, it serves no purpose to develop such evidence just to
assess cause and prejudice. See Shinn, 596 U. S., at ___
(slip op., at 20) (“when a federal habeas court . . . admits or
reviews new evidence for any purpose, it may not consider
that evidence on the merits of a negligent prisoner’s de-
faulted claim unless the exceptions in §2254(e)(2) are satis-
fied”). The District Court thus erred in ordering Twyford’s
transfer to gather evidence he had never demonstrated
would be admissible.
* * *
A transportation order that allows a prisoner to search
for new evidence is not “necessary or appropriate in aid of ”
a federal court’s adjudication of a habeas corpus action, 28
U. S. C. §1651(a), when the prisoner has not shown that the
desired evidence would be admissible in connection with a
particular claim for relief. Because the District Court en-
tered such an order despite Twyford’s failure to make the
required showing, the judgment of the Court of Appeals af-
firming that order is reversed and the case is remanded for
further proceedings consistent with this opinion.
It is so ordered.
Cite as: 596 U. S. ____ (2022) 1
BREYER, J., dissenting
SUPREME COURT OF THE UNITED STATES
_________________
No. 21–511
_________________
TIM SHOOP, WARDEN, PETITIONER v.
RAYMOND A. TWYFORD, III
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE SIXTH CIRCUIT
[June 21, 2022]
JUSTICE BREYER, with whom JUSTICE SOTOMAYOR and
JUSTICE KAGAN join, dissenting.
The Court today reviews a District Court’s pretrial order
requiring Ohio “to transport a prisoner in its custody to a
hospital for medical testing” in order to develop evidence to
support the prisoner’s habeas petition. Ante, at 1. The
Court holds that the District Court’s order did not comply
with the All Writs Act because the District Court failed to
consider whether the evidence sought could be admissible
in the habeas proceeding. See ante, at 9–10. I would not
reach the merits of that question because I do not believe
that the Court of Appeals had jurisdiction to hear the
State’s interlocutory appeal. I respectfully dissent.
I
Courts of Appeals generally have jurisdiction to review
“final decisions of the district courts.” 28 U. S. C. §1291.
They do not ordinarily hear interlocutory appeals. Limiting
appellate jurisdiction over interlocutory matters avoids
piecemeal decisionmaking and “combine[s] in one review all
stages of the proceeding that effectively may be reviewed
and corrected if and when final judgment results.” Cohen
v. Beneficial Industrial Loan Corp., 337 U. S. 541, 546
(1949). Too many interlocutory appeals could slow down
2 SHOOP v. TWYFORD
BREYER, J., dissenting
the workings of the judicial system. That can lead to a num-
ber of harms, including, e.g., “mak[ing] it more difficult for
trial judges to do their basic job—supervising trial proceed-
ings”; “threaten[ing] those proceedings with delay, adding
costs and diminishing coherence”; and “risk[ing] additional,
and unnecessary, appellate court work.” Johnson v. Jones,
515 U. S. 304, 309 (1995).
At the same time, interlocutory appeals can sometimes
have “important countervailing benefits.” Ibid. Balancing
the harms and benefits can be a difficult task, and Congress
has prescribed a means for accomplishing that task by way
of rulemaking. It has authorized this Court to promulgate
rules “defin[ing] when a ruling of a district court is final for
the purposes of appeal under section 1291,” §2072(c), and
“provid[ing] for an appeal of an interlocutory decision to the
courts of appeals that is not otherwise provided for” by stat-
ute, §1292(e). The State does not claim that any rule prom-
ulgated pursuant to this authority permits interlocutory
appeal of the transportation order here. Instead, the State
asks us to create such a rule by court decision, outside of
the congressionally prescribed rulemaking process.
It is true that, in the past, we have occasionally done so
under what we have called the “collateral order doctrine.”
That doctrine allows interlocutory appeal from a “small
class” of orders that “finally determine claims of right sep-
arable from, and collateral to, rights asserted in the action.”
Cohen, 337 U. S., at 546. But we have repeatedly stated
that this doctrine is a “ ‘narrow’ exception [that] should stay
that way and never be allowed to swallow the general rule
that a party is entitled to a single appeal, to be deferred
until final judgment has been entered.” Digital Equipment
Corp. v. Desktop Direct, Inc., 511 U. S. 863, 868 (1994) (ci-
tation omitted); see also Will v. Hallock, 546 U. S. 345, 350
(2006) (“[A]lthough the Court has been asked many times
to expand the ‘small class’ of collaterally appealable orders,
Cite as: 596 U. S. ____ (2022) 3
BREYER, J., dissenting
we have instead kept it narrow and selective in its member-
ship”); Mohawk Industries, Inc. v. Carpenter, 558 U. S. 100,
113 (2009) (“[R]ulemaking, ‘not expansion by court deci-
sion,’ [is] the preferred means for determining whether and
when prejudgment orders should be immediately appeala-
ble”).
We must therefore exercise caution before extending the
collateral order doctrine. We have “stringent[ly]” limited
that doctrine to only those district court orders “[1] that are
conclusive, [2] that resolve important questions completely
separate from the merits, and [3] that would render such
important questions effectively unreviewable on appeal
from final judgment in the underlying action.” Digital
Equipment Corp., 511 U. S., at 867–868.
II
A
The Court today extends the collateral order doctrine to
a new category of orders, which it describes as “[t]ranspor-
tation orders issued under the All Writs Act.” Ante, at 5,
n. 1. The Court believes these kinds of orders are collateral
and therefore immediately appealable because, it says, they
“(1) conclusively require transportation; (2) resolve an im-
portant question of state sovereignty conceptually distinct
from the merits of the prisoner’s claims; and (3) are entirely
unreviewable by the time the case has gone to final judg-
ment.” Ibid. (citation omitted). I agree that orders like the
one at issue here “conclusively require transportation” and
are largely “unreviewable by the time the case has gone to
final judgment.” Ibid. But I do not agree that such orders
“resolve an important question of state sovereignty concep-
tually distinct from the merits of the prisoner’s claims.”
Ibid. That is so for three reasons.
First, transportation orders do not appear to me to be es-
pecially “important.” Even if those orders are unreviewable
4 SHOOP v. TWYFORD
BREYER, J., dissenting
after final judgment, we have said that “the mere identifi-
cation of some interest that would be ‘irretrievably lost’ has
never sufficed,” on its own, to justify interlocutory appeal.
Digital Equipment Corp., 511 U. S., at 872. Rather, the or-
der must implicate “ ‘a substantial public interest’ or ‘some
particular value of a high order.’ ” Mohawk Industries, Inc.,
558 U. S., at 107. It is difficult to see how transportation
orders of the kind at issue here meet that requirement. The
order is analogous to a discovery order because it requires
the State to transport a prisoner for medical testing in order
to develop evidence relating to the prisoner’s habeas claims.
See ante, at 1, 7–8 (comparing requirements for a transpor-
tation order to requirements for discovery and for an evi-
dentiary hearing). I see no reason why such an order ordi-
narily should be of greater importance than a discovery
order of some other kind.
We have held that discovery orders are not immediately
appealable, even where discovery would require revealing
privileged information that, once shared, could not be un-
shared if the disclosing party prevailed on appeal after final
judgment. Mohawk Industries, Inc., 558 U. S., at 108–109.
Why should discovery-like transportation orders be imme-
diately appealable when ordinary discovery orders are not?
Neither touches upon substantial public interests. And, in
both instances, the harms of interlocutory appeal are sig-
nificant while the countervailing benefits are minimal.
Take first the harms. As I said above, interlocutory ap-
peals “unduly delay the resolution of district court litigation
and needlessly burden the courts of appeals.” See id., at
112. In this case, for example, the appeal of the District
Court’s transportation order has lasted over two years. See
App. to Pet. for Cert. 33a (order entered March 19, 2020).
If interlocutory appeals were permitted as of right in all
similar cases requiring transportation of a prisoner, the re-
sulting delays would impair the ability of district courts to
manage their own dockets and supervise trial proceedings.
Cite as: 596 U. S. ____ (2022) 5
BREYER, J., dissenting
By comparison, the benefits of interlocutory appeal here
are small. District courts, not appellate courts, have “com-
parative expertise” in deciding when evidentiary develop-
ment is appropriate and when transportation orders are
necessary to facilitate that development. See Johnson, 515
U. S., at 317. As a result, interlocutory appeal is unlikely
“to bring important error-correcting benefits” in most cases.
Id., at 316. In the rare case where an erroneous transpor-
tation order happens to implicate unusually important in-
terests, a State has other avenues for addressing that error.
It can ask district courts to certify a discretionary interloc-
utory appeal under §1292(b); seek a writ of mandamus; or
defy the order and incur a court-imposed sanction, which
may then itself be appealed immediately in some cases. See
Mohawk Industries Inc., 558 U. S., at 110–112. Those ave-
nues—sufficient to protect against errors in discovery, see
ibid.—should generally be sufficient for transportation-re-
lated errors as well.
Second, the Court overstates transportation orders’ im-
pact on “state sovereignty.” See ante, at 5, n. 1. The Court
of Appeals noted respondent’s argument that “discovery or-
ders generally are not appealable under the collateral-order
doctrine,” but it distinguished the transportation order at
issue here on the ground that it “implicates . . . a federal
court’s authority to compel state action.” 11 F. 4th 518, 523
(CA6 2021). But the mere fact that the appealing party is
a State is not, on its own, enough to justify interlocutory
appeal. We have never suggested, for example, that a dis-
covery order against a State is immediately appealable
simply because it imposes costs on a sovereign State. To
allow interlocutory appeal on such grounds would create an
anomaly: The State would be able to immediately appeal a
discovery order entered against it, but an opposing party
would not.
The Court suggests that the transportation order here is
not a mere discovery order because it “requir[es] a State to
6 SHOOP v. TWYFORD
BREYER, J., dissenting
take a convicted felon outside the prison’s walls.” Ante, at
5, n. 1. The Court says doing so “creates public safety risks
and burdens on the State that cannot be remedied after fi-
nal judgment.” Ibid. But what exactly are those risks? The
order here requires transporting respondent to a medical
center—the Ohio State University Wexner Medical Center.
11 F. 4th, at 520. That medical center is the “official prison
hospital,” which “has the security and other infrastructure”
to safely accommodate prisoners and does so regularly.
App. to Pet. for Cert. 24a; Tr. of Oral Arg. 40, 57–58. Re-
spondent tells us that he has personally been transported
between the prison and the medical center 16 times without
incident. Id., at 57.
Other orders might well create similar kinds of risks. A
writ of habeas corpus might require the State to transport
a prisoner to court to testify or for trial, see §2241(c)(5), or
an order appointing a psychiatrist or other expert to con-
duct a psychological examination might require the State to
allow access to a dangerous prisoner, see Fed. Rule Civ.
Proc. 35(a). Would the Court’s logic require that all such
orders with security risks be immediately appealable? That
would be a dramatic extension of the collateral order doc-
trine, which we have said should remain “ ‘narrow,’ ” Digital
Equipment Corp., 511 U. S., at 868 (emphasis added).
Finally, we have also said that some interlocutory ap-
peals “mak[e] unwise use of appellate courts’ time, by forc-
ing them to decide in the context of a less developed record,
an issue very similar to one they may well decide anyway
later, on a record that will permit a better decision.” John-
son, 515 U. S., at 317. That warning is applicable here. The
question whether the transportation order was proper un-
der the All Writs Act is not conceptually distinct from the
merits of respondent’s habeas claims. In order to obtain a
transportation order, the Court says, a prisoner must show
that “the desired evidence would be admissible in connec-
tion with a particular claim for relief.” Ante, at 11. Of
Cite as: 596 U. S. ____ (2022) 7
BREYER, J., dissenting
course, at this early stage, a district court’s assessment of
that issue is only preliminary because it cannot know for
certain what evidence will be revealed. After the evidence
is developed, the court will need to make a final determina-
tion of whether it is in fact admissible. Requiring appellate
courts to review both the district court’s preliminary assess-
ment of admissibility on interlocutory appeal and its ulti-
mate assessment of the same question after final judgment
is unnecessarily duplicative and inefficient.
All of these concerns suggest that transportation orders
like the one here do not satisfy the requirements for inter-
locutory appeal under the collateral order doctrine.
B
The Court points out in response that “[e]very Court of
Appeals to consider the question” has found a transporta-
tion order to be immediately appealable. Ante, at 5, n. 1.
True. But few Courts of Appeals have been asked to “con-
sider the question.” The Court cites, over the last five dec-
ades, only four cases (besides this one) that have concluded
that transportation orders are immediately appealable.
Ibid. (citing Jones v. Lilly, 37 F. 3d 964, 965–966 (CA3
1994); Jackson v. Vasquez, 1 F. 3d 885, 887–888 (CA9
1993); Ballard v. Spradley, 557 F. 2d 476, 479 (CA5 1977);
Barnes v. Black, 544 F. 3d 807, 810–811 (CA7 2008)). An
average of one decision every decade can hardly be thought
to establish a lower court consensus. A contrary determi-
nation here would not disturb settled practice.
The Court also asserts that, on one occasion, we have pre-
viously reviewed a transportation order. See Pennsylvania
Bureau of Correction v. United States Marshals Service, 474
U. S. 34 (1985). But the precedential value of that decision
is limited because the opinion did not discuss the Court of
Appeals’ jurisdiction to hear an interlocutory appeal from
the order. See Arbaugh v. Y & H Corp., 546 U. S. 500, 511
(2006). It does not set forth a jurisdictional ruling at all.
8 SHOOP v. TWYFORD
BREYER, J., dissenting
* * *
For these reasons, I would not reach the merits of the
questions presented by petitioner. I respectfully dissent.
Cite as: 596 U. S. ____ (2022) 1
GORSUCH, J., dissenting
SUPREME COURT OF THE UNITED STATES
_________________
No. 21–511
_________________
TIM SHOOP, WARDEN, PETITIONER v.
RAYMOND A. TWYFORD, III
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE SIXTH CIRCUIT
[June 21, 2022]
JUSTICE GORSUCH, dissenting.
The Court granted review to decide whether and under
what circumstances a federal district court may order a
State to transport a prisoner to a hospital for testing. Later,
however, it became clear a potential jurisdictional defect
threatened to preclude the Court from reaching that ques-
tion. The District Court’s transportation ruling was an in-
terlocutory order, not a final judgment. To address its mer-
its, the Court would first have to extend the collateral order
doctrine to a new class of cases. See Cohen v. Beneficial
Industrial Loan Corp., 337 U. S. 541, 545–547 (1949). In a
terse footnote today, the Court does just that. Ante, at 5,
n. 1.
Respectfully, I would have dismissed this case as improv-
idently granted when the jurisdictional complication be-
came apparent. We did not take this case to extend Cohen.
And this Court has repeatedly “admoni[shed]” other courts
to keep “the class of collaterally appealable orders . . . ‘nar-
row and selective.’ ” Mohawk Industries, Inc. v. Carpenter,
558 U. S. 100, 113 (2009). If anything, this call for caution
“has acquired special force in recent years with the enact-
ment of legislation designating rulemaking . . . as the pre-
ferred means for determining whether and when prejudg-
ment orders should be immediately appealable.” Ibid.