(Slip Opinion)              OCTOBER TERM, 2018                                       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

    BUCKLEW v. PRECYTHE, DIRECTOR, MISSOURI
       DEPARTMENT OF CORRECTIONS, ET AL.

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

    No. 17–8151. Argued November 6, 2018—Decided April 1, 2019
In Baze v. Rees, 553 U. S. 35, a plurality of this Court concluded that a
  State’s refusal to alter its execution protocol could violate the Eighth
  Amendment only if an inmate first identified a “feasible, readily im-
  plemented” alternative procedure that would “significantly reduce a
  substantial risk of severe pain.” Id., at 52. A majority of the Court
  subsequently held Baze’s plurality opinion to be controlling. See
  Glossip v. Gross, 576 U. S. ___.
     Petitioner Russell Bucklew was convicted of murder and sentenced
  to death. The State of Missouri plans to execute him by lethal injec-
  tion using a single drug, pentobarbital. Mr. Bucklew presented an
  as-applied Eighth Amendment challenge to the State’s lethal injec-
  tion protocol, alleging that, regardless whether it would cause excru-
  ciating pain for all prisoners, it would cause him severe pain because
  of his particular medical condition.
     The District Court dismissed his challenge. The Eighth Circuit,
  applying the Baze-Glossip test, remanded the case to allow Mr. Buck-
  lew to identify a feasible, readily implemented alternative procedure
  that would significantly reduce his alleged risk of pain. Eventually,
  Mr. Bucklew identified nitrogen hypoxia, but the District Court found
  the proposal lacking and granted the State’s motion for summary
  judgment. The Eighth Circuit affirmed.
Held:
    1. Baze and Glossip govern all Eighth Amendment challenges,
 whether facial or as-applied, alleging that a method of execution in-
 flicts unconstitutionally cruel pain. Pp. 8–20.
       (a) The Eighth Amendment forbids “cruel and unusual” methods
 of capital punishment but does not guarantee a prisoner a painless
2                        BUCKLEW v. PRECYTHE

                                  Syllabus

    death. See Glossip, 576 U. S., at ___. As originally understood, the
    Eighth Amendment tolerated methods of execution, like hanging,
    that involved a significant risk of pain, while forbidding as cruel only
    those methods that intensified the death sentence by “superadding”
    terror, pain, or disgrace. To establish that a State’s chosen method
    cruelly “superadds” pain to the death sentence, a prisoner must show
    a feasible and readily implemented alternative method that would
    significantly reduce a substantial risk of severe pain and that the
    State has refused to adopt without a legitimate penological reason.
    Baze, 553 U. S., at 52; Glossip, 576 U. S., at ___. And Glossip left no
    doubt that this standard governs “all Eighth Amendment method-of-
    execution claims.” Id., at ___. Baze and Glossip recognized that the
    Constitution affords a “measure of deference to a State’s choice of ex-
    ecution procedures” and does not authorize courts to serve as “boards
    of inquiry charged with determining ‘best practices’ for executions.”
    Baze, 553 U. S., at 51–52. Nor do they suggest that traditionally ac-
    cepted methods of execution are necessarily rendered unconstitution-
    al as soon as an arguably more humane method becomes available.
    Pp. 8–14.
          (b) Precedent forecloses Mr. Bucklew’s argument that methods
    posing a “substantial and particular risk of grave suffering” when
    applied to a particular inmate due to his “unique medical condition”
    should be considered “categorically” cruel. Because distinguishing
    between constitutionally permissible and impermissible degrees of
    pain is a necessarily comparative exercise, the Court held in Glossip,
    identifying an available alternative is “a requirement of all Eighth
    Amendment method-of-execution claims” alleging cruel pain. 576
    U. S., at ___. Mr. Bucklew’s argument is also inconsistent with the
    original and historical understanding of the Eighth Amendment on
    which Baze and Glossip rest: When it comes to determining whether
    a punishment is unconstitutionally cruel because of the pain in-
    volved, the law has always asked whether the punishment superadds
    pain well beyond what’s needed to effectuate a death sentence. And
    answering that question has always involved a comparison with
    available alternatives, not an abstract exercise in “categorical” classi-
    fication. The substantive meaning of the Eighth Amendment does
    not change depending on how broad a remedy the plaintiff chooses to
    seek. Mr. Bucklew’s solution also invites pleading games, and there
    is little likelihood that an inmate facing a serious risk of pain will be
    unable to identify an available alternative. Pp. 14–20.
       2. Mr. Bucklew has failed to satisfy the Baze-Glossip test. Pp. 20–
    28.
          (a) He fails for two independent reasons to present a triable
    question on the viability of nitrogen hypoxia as an alternative to the
                     Cite as: 587 U. S. ____ (2019)                     3

                                Syllabus

  State’s lethal injection protocol. First, an inmate must show that his
  proposed alternative method is not just theoretically “feasible” but al-
  so “ ‘readily implemented,’ ” Glossip, 576 U. S., at ___–___. This
  means the inmate’s proposal must be sufficiently detailed to permit a
  finding that the State could carry it out relatively easily and reason-
  ably quickly. Mr. Bucklew’s proposal falls well short of that stand-
  ard. He presented no evidence on numerous questions essential to
  implementing his preferred method; instead, he merely pointed to re-
  ports from correctional authorities in other States indicating the need
  for additional study to develop a nitrogen hypoxia protocol. Second,
  the State had a “legitimate” reason for declining to switch from its
  current method of execution as a matter of law, Baze, 553 U. S., at
  52, namely, choosing not to be the first to experiment with a new,
  “untried and untested” method of execution. Id., at 41. Pp. 20–22.
       (b) Even if nitrogen hypoxia were a viable alternative, neither of
  Mr. Bucklew’s theories shows that nitrogen hypoxia would signifi-
  cantly reduce a substantial risk of severe pain. First, his contention
  that the State may use painful procedures to administer the lethal
  injection, including forcing him to lie flat on his back (which he
  claims could impair his breathing even before the pentobarbital is
  administered), rests on speculation unsupported, if not affirmatively
  contradicted, by the record. And to the extent the record is unclear,
  he had ample opportunity to conduct discovery and develop a factual
  record concerning the State’s planned procedures. Second, Mr. Buck-
  lew contends that while either method will cause him to experience
  feelings of suffocation for some period of time before he is rendered
  fully unconscious, the duration of that period will be shorter with ni-
  trogen than with pentobarbital. But nothing in the record suggests
  that he will be capable of experiencing pain for significantly more
  time after receiving pentobarbital than he would after receiving ni-
  trogen. His claim to the contrary rested on his expert’s testimony re-
  garding a study of euthanasia in horses that everyone now agrees the
  expert misunderstood or misremembered. Pp. 23–28.
883 F. 3d 1087, affirmed.

  GORSUCH, J., delivered the opinion of the Court, in which ROBERTS,
C. J., and THOMAS, ALITO, and KAVANAUGH, JJ., joined. THOMAS, J., and
KAVANAUGH, J., filed concurring opinions. BREYER, J., filed a dissenting
opinion, in which GINSBURG, SOTOMAYOR, and KAGAN, JJ., joined as to
all but Part III. SOTOMAYOR, J., filed a dissenting opinion.
                        Cite as: 587 U. S. ____ (2019)                              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. 17–8151
                                   _________________


   RUSSELL BUCKLEW, PETITIONER v. ANNE L.
 PRECYTHE, DIRECTOR, MISSOURI DEPARTMENT
           OF CORRECTIONS, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
           APPEALS FOR THE EIGHTH CIRCUIT
                                 [April 1, 2019]

   JUSTICE GORSUCH delivered the opinion of the Court.
   Russell Bucklew concedes that the State of Missouri
lawfully convicted him of murder and a variety of other
crimes. He acknowledges that the U. S. Constitution
permits a sentence of execution for his crimes. He accepts,
too, that the State’s lethal injection protocol is constitu-
tional in most applications. But because of his unusual
medical condition, he contends the protocol is unconstitu-
tional as applied to him. Mr. Bucklew raised this claim for
the first time less than two weeks before his scheduled
execution. He received a stay of execution and five years
to pursue the argument, but in the end neither the district
court nor the Eighth Circuit found it supported by the law
or evidence. Now, Mr. Bucklew asks us to overturn those
judgments. We can discern no lawful basis for doing so.
                            I
                            A
  In 1996, when Stephanie Ray announced that she wanted
to end their relationship, Mr. Bucklew grew violent. He
cut her jaw, punched her in the face, and threatened her
2                  BUCKLEW v. PRECYTHE

                      Opinion of the Court

with a knife. Frightened to remain in the home they had
shared, Ms. Ray sought refuge with her children in Mi-
chael Sanders’ nearby residence. But then one night Mr.
Bucklew invaded that home. Bearing a pistol in each
hand, he shot Mr. Sanders in the chest; fired at Mr. Sand-
ers’ 6-year-old son (thankfully, he missed); and pistol-
whipped Ms. Ray, this time breaking her jaw. Then Mr.
Bucklew handcuffed Ms. Ray, drove her to a secluded spot,
and raped her at gunpoint. After a trooper spotted Mr.
Bucklew, a shootout followed and he was finally arrested.
While all this played out, Mr. Sanders bled to death. As a
coda, Mr. Bucklew escaped from jail while awaiting trial
and attacked Ms. Ray’s mother with a hammer before he
could be recaptured.
  After a decade of litigation, Mr. Bucklew was seemingly
out of legal options. A jury had convicted him of murder
and other crimes and recommended a death sentence,
which the court had imposed. His direct appeal had
proved unsuccessful. State v. Bucklew, 973 S. W. 2d 83
(Mo. 1998), cert. denied, 525 U. S. 1082 (1999). Separate
rounds of state and federal post-conviction proceedings
also had failed to yield relief. Bucklew v. State, 38 S. W.
3d 395 (Mo.), cert. denied, 534 U. S. 964 (2001); Bucklew v.
Luebbers, 436 F. 3d 1010 (CA8), cert. denied, 549 U. S.
1079 (2006).
                              B
  As it turned out, though, Mr. Bucklew’s case soon be-
came caught up in a wave of litigation over lethal injection
procedures. Like many States, Missouri has periodically
sought to improve its administration of the death penalty.
Early in the 20th century, the State replaced hanging with
the gas chamber. Later in the century, it authorized the
use of lethal injection as an alternative to lethal gas. By
the time Mr. Bucklew’s post-conviction proceedings ended,
Missouri’s protocol called for lethal injections to be carried
                 Cite as: 587 U. S. ____ (2019)            3

                     Opinion of the Court

out using three drugs: sodium thiopental, pancuronium
bromide, and potassium chloride. And by that time, too,
various inmates were in the process of challenging the
constitutionality of the State’s protocol and others like it
around the country. See Taylor v. Crawford, 457 F. 3d
902 (CA8 2006); Note, A New Test for Evaluating Eighth
Amendment Challenges to Lethal Injections, 120 Harv.
L. Rev. 1301, 1304 (2007) (describing flood of lethal injec-
tion lawsuits around 2006 that “severely constrained
states’ ability to carry out executions”); Denno, The Lethal
Injection Quandary: How Medicine Has Dismantled the
Death Penalty, 76 Ford. L. Rev. 49, 102–116 (2007).
   Ultimately, this Court answered these legal challenges
in Baze v. Rees, 553 U. S. 35 (2008). Addressing Ken-
tucky’s similar three-drug protocol, THE CHIEF JUSTICE,
joined by JUSTICE ALITO and Justice Kennedy, concluded
that a State’s refusal to alter its lethal injection protocol
could violate the Eighth Amendment only if an inmate
first identified a “feasible, readily implemented” alterna-
tive procedure that would “significantly reduce a substan-
tial risk of severe pain.” Id., at 52. JUSTICE THOMAS,
joined by Justice Scalia, thought the protocol passed mus-
ter because it was not intended “to add elements of terror,
pain, or disgrace to the death penalty.” Id., at 107.
JUSTICE BREYER reached the same result because he saw
no evidence that the protocol created “a significant risk of
unnecessary suffering.” Id., at 113. And though Justice
Stevens objected to the continued use of the death penalty,
he agreed that petitioners’ evidence was insufficient. Id.,
at 87. After this Court decided Baze, it denied review in a
case seeking to challenge Missouri’s similar lethal injec-
tion protocol. Taylor v. Crawford, 487 F. 3d 1072 (2007),
cert. denied, 553 U. S. 1004 (2008).
   But that still was not the end of it. Next, Mr. Bucklew
and other inmates unsuccessfully challenged Missouri’s
protocol in state court, alleging that it had been adopted in
4                  BUCKLEW v. PRECYTHE

                     Opinion of the Court

contravention of Missouri’s Administrative Procedure Act.
Middleton v. Missouri Dept. of Corrections, 278 S. W. 3d
193 (Mo.), cert. denied, 556 U. S. 1255 (2009). They also
unsuccessfully challenged the protocol in federal court,
this time alleging it was pre-empted by various federal
statutes. Ringo v. Lombardi, 677 F. 3d 793 (CA8 2012).
And Mr. Bucklew sought to intervene in yet another law-
suit alleging that Missouri’s protocol violated the Eighth
Amendment because unqualified personnel might botch its
administration. That lawsuit failed too. Clemons v. Craw-
ford, 585 F. 3d 1119 (CA8 2009), cert. denied, 561 U. S.
1026 (2010).
  While all this played out, pressure from anti-death-
penalty advocates induced the company that manufac-
tured sodium thiopental to stop supplying it for use in
executions. As a result, the State was unable to proceed
with executions until it could change its lethal injection
protocol again. This it did in 2012, prescribing the use of a
single drug, the sedative propofol. Soon after that, Mr.
Bucklew and other inmates sued to invalidate this new
protocol as well, alleging that it would produce excruciat-
ing pain and violate the Eighth Amendment on its face.
After the State revised the protocol in 2013 to use the
sedative pentobarbital instead of propofol, the inmates
amended their complaint to allege that pentobarbital
would likewise violate the Constitution.
                              C
  Things came to a head in 2014. With its new protocol in
place and the necessary drugs now available, the State
scheduled Mr. Bucklew’s execution for May 21. But 12
days before the execution Mr. Bucklew filed yet another
lawsuit, the one now before us. In this case, he presented
an as-applied Eighth Amendment challenge to the State’s
new protocol. Whether or not it would cause excruciating
pain for all prisoners, as his previous lawsuit alleged, Mr.
                 Cite as: 587 U. S. ____ (2019)           5

                     Opinion of the Court

Bucklew now contended that the State’s protocol would
cause him severe pain because of his particular medical
condition. Mr. Bucklew suffers from a disease called
cavernous hemangioma, which causes vascular tumors—
clumps of blood vessels—to grow in his head, neck, and
throat. His complaint alleged that this condition could
prevent the pentobarbital from circulating properly in his
body; that the use of a chemical dye to flush the intrave-
nous line could cause his blood pressure to spike and his
tumors to rupture; and that pentobarbital could interact
adversely with his other medications.
   These latest protocol challenges yielded mixed results.
The district court dismissed both the inmates’ facial chal-
lenge and Mr. Bucklew’s as-applied challenge. But, at Mr.
Bucklew’s request, this Court agreed to stay his execution
until the Eighth Circuit could hear his appeal. Bucklew v.
Lombardi, 572 U. S. 1131 (2014). Ultimately, the Eighth
Circuit affirmed the dismissal of the facial challenge. Zink
v. Lombardi, 783 F. 3d 1089 (en banc) (per curiam), cert.
denied, 576 U. S. ___ (2015). Then, turning to the as-
applied challenge and seeking to apply the test set forth
by the Baze plurality, the court held that Mr. Bucklew’s
complaint failed as a matter of law to identify an alterna-
tive procedure that would significantly reduce the risks he
alleged would flow from the State’s lethal injection proto-
col. Yet, despite this dispositive shortcoming, the court of
appeals decided to give Mr. Bucklew another chance to
plead his case. The court stressed that, on remand before
the district court, Mr. Bucklew had to identify “at the
earliest possible time” a feasible, readily implemented
alternative procedure that would address those risks.
Bucklew v. Lombardi, 783 F. 3d 1120, 1127–1128 (2015)
(en banc).
   Shortly after the Eighth Circuit issued its judgment,
this Court decided Glossip v. Gross, 576 U. S. ___ (2015),
rejecting a challenge to Oklahoma’s lethal injection proto-
6                  BUCKLEW v. PRECYTHE

                      Opinion of the Court

col. There, the Court clarified that THE CHIEF JUSTICE’s
plurality opinion in Baze was controlling under Marks v.
United States, 430 U. S. 188 (1977). In doing so, it reaf-
firmed that an inmate cannot successfully challenge a
method of execution under the Eighth Amendment unless
he identifies “an alternative that is ‘feasible, readily im-
plemented, and in fact significantly reduces a substantial
risk of severe pain.’ ” 576 U. S., at ___–___ (slip op., at 12–
13). JUSTICE THOMAS, joined by Justice Scalia, reiterated
his view that the Eighth Amendment “prohibits only those
methods of execution that are deliberately designed to
inflict pain,” but he joined the Court’s opinion because it
correctly explained why petitioners’ claim failed even
under the controlling opinion in Baze. Glossip, 576 U. S.,
at ___ (concurring opinion) (slip op., at 1) (internal quota-
tion marks and alterations omitted).
                               D
  Despite the Eighth Circuit’s express instructions, when
Mr. Bucklew returned to the district court in 2015 he still
refused to identify an alternative procedure that would
significantly reduce his alleged risk of pain. Instead, he
insisted that inmates should have to carry this burden
only in facial, not as-applied, challenges. Finally, after the
district court gave him “one last opportunity,” App. 30, Mr.
Bucklew filed a fourth amended complaint in which he
claimed that execution by “lethal gas” was a feasible and
available alternative method that would significantly
reduce his risk of pain. Id., at 42. Mr. Bucklew later
clarified that the lethal gas he had in mind was nitrogen,
which neither Missouri nor any other State had ever used
to carry out an execution.
  The district court allowed Mr. Bucklew “extensive dis-
covery” on his new proposal. 883 F. 3d 1087, 1094 (CA8
2018). But even at the close of discovery in 2017, the
district court still found the proposal lacking and granted
                 Cite as: 587 U. S. ____ (2019)           7

                     Opinion of the Court

the State’s motion for summary judgment. By this point
in the proceedings, Mr. Bucklew’s contentions about the
pain he might suffer had evolved considerably. He no
longer complained about circulation of the drug, the use of
dye, or adverse drug interactions. Instead, his main claim
now was that he would experience pain during the period
after the pentobarbital started to take effect but before it
rendered him fully unconscious. According to his expert,
Dr. Joel Zivot, while in this semiconscious “twilight stage”
Mr. Bucklew would be unable to prevent his tumors from
obstructing his breathing, which would make him feel like
he was suffocating. Dr. Zivot declined to say how long this
twilight stage would last. When pressed, however, he
referenced a study on euthanasia in horses. He claimed
that the horses in the study had displayed some amount of
brain activity, as measured with an electroencephalogram
(or EEG), for up to four minutes after they were given a
large dose of pentobarbital. Based on Dr. Zivot’s testi-
mony, the district court found a triable issue as to whether
there was a “substantial risk” that Mr. Bucklew would
“experience choking and an inability to breathe for up to
four minutes” if he were executed by lethal injection. App.
827. Even so, the court held, Mr. Bucklew’s claim failed
because he had produced no evidence that his proposed
alternative, execution by nitrogen hypoxia, would signifi-
cantly reduce that risk.
   This time, a panel of the Eighth Circuit affirmed. The
panel held that Mr. Bucklew had produced no evidence
that the risk of pain he alleged “would be substantially
reduced by use of nitrogen hypoxia instead of lethal injec-
tion as the method of execution.” 883 F. 3d, at 1096.
Judge Colloton dissented, arguing that the evidence raised
a triable issue as to whether nitrogen gas would “render
Bucklew insensate more quickly than pentobarbital.” Id.,
at 1099. The full court denied rehearing en banc over a
dissent by Judge Kelly, who maintained that, while pris-
8                  BUCKLEW v. PRECYTHE

                      Opinion of the Court

oners pursuing facial challenges to a state execution pro-
tocol must plead and prove an alternative method of exe-
cution under Baze and Glossip, prisoners like Mr. Bucklew
who pursue as-applied challenges should not have to bear
that burden. 885 F. 3d 527, 528 (2018).
   On the same day Mr. Bucklew was scheduled to be
executed, this Court granted him a second stay of execu-
tion. 583 U. S. ___ (2018). We then agreed to hear his
case to clarify the legal standards that govern an as-
applied Eighth Amendment challenge to a State’s method
of carrying out a death sentence. 584 U. S. ___ (2018).
                              II
  We begin with Mr. Bucklew’s suggestion that the test
for lethal injection protocol challenges announced in Baze
and Glossip should govern only facial challenges, not as-
applied challenges like his. In evaluating this argument,
we first examine the original and historical understanding
of the Eighth Amendment and our precedent in Baze and
Glossip. We then address whether, in light of those au-
thorities, it would be appropriate to adopt a different
constitutional test for as-applied claims.
                               A
   The Constitution allows capital punishment. See Glos-
sip, 576 U. S., at ___–___ (slip op., at 2–4); Baze, 553 U. S.,
at 47. In fact, death was “the standard penalty for all
serious crimes” at the time of the founding. S. Banner,
The Death Penalty: An American History 23 (2002) (Ban-
ner). Nor did the later addition of the Eighth Amendment
outlaw the practice. On the contrary—the Fifth Amend-
ment, added to the Constitution at the same time as the
Eighth, expressly contemplates that a defendant may be
tried for a “capital” crime and “deprived of life” as a pen-
alty, so long as proper procedures are followed. And the
First Congress, which proposed both Amendments, made a
                 Cite as: 587 U. S. ____ (2019)           9

                     Opinion of the Court

number of crimes punishable by death. See Act of Apr. 30,
1790, 1 Stat. 112. Of course, that doesn’t mean the Ameri-
can people must continue to use the death penalty. The
same Constitution that permits States to authorize capital
punishment also allows them to outlaw it. But it does
mean that the judiciary bears no license to end a debate
reserved for the people and their representatives.
   While the Eighth Amendment doesn’t forbid capital
punishment, it does speak to how States may carry out
that punishment, prohibiting methods that are “cruel and
unusual.” What does this term mean? At the time of the
framing, English law still formally tolerated certain pun-
ishments even though they had largely fallen into disuse—
punishments in which “terror, pain, or disgrace [were]
superadded” to the penalty of death. 4 W. Blackstone,
Commentaries on the Laws of England 370 (1769). These
included such “[d]isgusting” practices as dragging the
prisoner to the place of execution, disemboweling, quarter-
ing, public dissection, and burning alive, all of which
Blackstone observed “savor[ed] of torture or cruelty.” Ibid.
   Methods of execution like these readily qualified as
“cruel and unusual,” as a reader at the time of the Eighth
Amendment’s adoption would have understood those
words. They were undoubtedly “cruel,” a term often de-
fined to mean “[p]leased with hurting others; inhuman;
hard-hearted; void of pity; wanting compassion; savage;
barbarous; unrelenting,” 1 S. Johnson, A Dictionary of the
English Language (4th ed. 1773), or “[d]isposed to give
pain to others, in body or mind; willing or pleased to tor-
ment, vex or afflict; inhuman; destitute of pity, compassion
or kindness,” 1 N. Webster, An American Dictionary of the
English Language (1828). And by the time of the found-
ing, these methods had long fallen out of use and so had
become “unusual.” 4 Blackstone, supra, at 370; Banner
76; Baze, 553 U. S., at 97 (THOMAS, J., concurring in
judgment); see also Stinneford, The Original Meaning of
10                 BUCKLEW v. PRECYTHE

                     Opinion of the Court

“Unusual”: The Eighth Amendment as a Bar to Cruel
Innovation, 102 Nw. U. L. Rev. 1739, 1770–1771, 1814
(2008) (observing that Americans in the late 18th and
early 19th centuries described as “unusual” governmental
actions that had “fall[en] completely out of usage for a long
period of time”).
  Contemporary evidence confirms that the people who
ratified the Eighth Amendment would have understood it
in just this way. Patrick Henry, for one, warned that
unless the Constitution was amended to prohibit “cruel
and unusual punishments,” Congress would be free to
inflict “tortures” and “barbarous” punishments. 3 Debates
on the Federal Constitution 447–448 (J. Elliot 2d ed.
1891). Many early commentators likewise described the
Eighth Amendment as ruling out “the use of the rack or
the stake, or any of those horrid modes of torture devised
by human ingenuity for the gratification of fiendish pas-
sion.” J. Bayard, A Brief Exposition of the Constitution of
the United States 140 (1833); see B. Oliver, The Rights of
an American Citizen 186 (1832) (the Eighth Amendment
prohibits such “barbarous and cruel punishments” as
“[b]reaking on the wheel, flaying alive, rending asunder
with horses, . . . maiming, mutilating and scourging to
death”). Justice Story even remarked that he thought the
prohibition of cruel and unusual punishments likely “un-
necessary” because no “free government” would ever au-
thorize “atrocious” methods of execution like these. 3 J.
Story, Commentaries on the Constitution of the United
States §1896, p. 750 (1833).
  Consistent with the Constitution’s original understand-
ing, this Court in Wilkerson v. Utah, 99 U. S. 130 (1879),
permitted an execution by firing squad while observing
that the Eighth Amendment forbade the gruesome meth-
ods of execution described by Blackstone “and all others in
the same line of unnecessary cruelty.” Id., at 135–136. A
few years later, the Court upheld a sentence of death by
                 Cite as: 587 U. S. ____ (2019)           11

                     Opinion of the Court

electrocution while observing that, though electrocution
was a new mode of punishment and therefore perhaps
could be considered “unusual,” it was not “cruel” in the
constitutional sense: “[T]he punishment of death is not
cruel, within the meaning of that word as used in the
Constitution. [Cruelty] implies . . . something inhuman
and barbarous, something more than the mere extin-
guishment of life.” In re Kemmler, 136 U. S. 436, 447
(1890).
   It’s instructive, too, to contrast the modes of execution
the Eighth Amendment was understood to forbid with
those it was understood to permit. At the time of the
Amendment’s adoption, the predominant method of execu-
tion in this country was hanging. Glossip, 576 U. S., at
___ (slip op., at 2). While hanging was considered more
humane than some of the punishments of the Old World,
it was no guarantee of a quick and painless death. “Many
and perhaps most hangings were evidently painful for the
condemned person because they caused death slowly,” and
“[w]hether a hanging was painless or painful seems to
have been largely a matter of chance.” Banner 48, 170.
The force of the drop could break the neck and sever the
spinal cord, making death almost instantaneous. But that
was hardly assured given the techniques that prevailed at
the time. More often it seems the prisoner would die from
loss of blood flow to the brain, which could produce uncon-
sciousness usually within seconds, or suffocation, which
could take several minutes. Id., at 46–47; J. Laurence,
The History of Capital Punishment 44–46 (1960); Gard-
ner, Executions and Indignities: An Eighth Amendment
Assessment of Methods of Inflicting Capital Punishment,
39 Ohio St. L. J. 96, 120 (1978). But while hanging could
and often did result in significant pain, its use “was virtu-
ally never questioned.” Banner 170. Presumably that was
because, in contrast to punishments like burning and
disemboweling, hanging wasn’t “intended to be painful”
12                  BUCKLEW v. PRECYTHE

                       Opinion of the Court

and the risk of pain involved was considered “unfortunate
but inevitable.” Ibid.; see also id., at 48.
  What does all this tell us about how the Eighth
Amendment applies to methods of execution? For one
thing, it tells us that the Eighth Amendment does not
guarantee a prisoner a painless death—something that, of
course, isn’t guaranteed to many people, including most
victims of capital crimes. Glossip, 576 U. S., at ___ (slip
op., at 4). Instead, what unites the punishments the
Eighth Amendment was understood to forbid, and distin-
guishes them from those it was understood to allow, is
that the former were long disused (unusual) forms of
punishment that intensified the sentence of death with a
(cruel) “ ‘superadd[ition]’ ” of “ ‘terror, pain, or disgrace.’ ”
Baze, 553 U. S., at 48; accord, id., at 96 (THOMAS, J., con-
curring in judgment).
  This Court has yet to hold that a State’s method of
execution qualifies as cruel and unusual, and perhaps
understandably so. Far from seeking to superadd terror,
pain, or disgrace to their executions, the States have often
sought more nearly the opposite, exactly as Justice Story
predicted. Through much of the 19th century, States
experimented with technological innovations aimed at
making hanging less painful. See Banner 170–177. In the
1880s, following the recommendation of a commission
tasked with finding “ ‘the most humane and practical
method known to modern science of carrying into effect
the sentence of death,’ ” the State of New York replaced
hanging with electrocution. Glossip, 576 U. S., at ___ (slip
op., at 2). Several States followed suit in the “ ‘ “belief that
electrocution is less painful and more humane than hang-
ing.” ’ ” Ibid. Other States adopted lethal gas after con-
cluding it was “ ‘the most humane [method of execution]
known to modern science.’ ” Ibid. And beginning in the
1970s, the search for less painful modes of execution led
many States to switch to lethal injection. Id., at ___ (slip
                 Cite as: 587 U. S. ____ (2019)           13

                     Opinion of the Court

op., at 3); Baze, 553 U. S., at 42, 62; see also Banner 178–
181, 196–197, 297. Notably, all of these innovations oc-
curred not through this Court’s intervention, but through
the initiative of the people and their representatives.
   Still, accepting the possibility that a State might try to
carry out an execution in an impermissibly cruel and
unusual manner, how can a court determine when a State
has crossed the line? THE CHIEF JUSTICE’s opinion in
Baze, which a majority of the Court held to be controlling
in Glossip, supplies critical guidance. It teaches that
where (as here) the question in dispute is whether the
State’s chosen method of execution cruelly superadds pain
to the death sentence, a prisoner must show a feasible and
readily implemented alternative method of execution that
would significantly reduce a substantial risk of severe
pain and that the State has refused to adopt without a
legitimate penological reason. See Glossip, 576 U. S., at
___–___ (slip op., at 12–13); Baze, 553 U. S., at 52. Glossip
left no doubt that this standard governs “all Eighth
Amendment method-of-execution claims.” 576 U. S., at
___ (slip op., at 1).
   In reaching this conclusion, Baze and Glossip recognized
that the Eighth Amendment “does not demand the avoid-
ance of all risk of pain in carrying out executions.” Baze,
553 U. S., at 47. To the contrary, the Constitution affords
a “measure of deference to a State’s choice of execution
procedures” and does not authorize courts to serve as
“boards of inquiry charged with determining ‘best practices’
for executions.” Id., at 51–52, and nn. 2–3. The Eighth
Amendment does not come into play unless the risk of
pain associated with the State’s method is “substantial
when compared to a known and available alternative.”
Glossip, 576 U. S., at ___ (slip op., at 13); see Baze, 553
U. S., at 61. Nor do Baze and Glossip suggest that tradi-
tionally accepted methods of execution—such as hanging,
the firing squad, electrocution, and lethal injection—are
14                 BUCKLEW v. PRECYTHE

                     Opinion of the Court

necessarily rendered unconstitutional as soon as an argu-
ably more humane method like lethal injection becomes
available. There are, the Court recognized, many legiti-
mate reasons why a State might choose, consistent with
the Eighth Amendment, not to adopt a prisoner’s pre-
ferred method of execution. See, e.g., Glossip, 576 U. S., at
___–___ (slip op., at 13–14) (a State can’t be faulted for
failing to use lethal injection drugs that it’s unable to
procure through good-faith efforts); Baze, 553 U. S., at 57
(a State has a legitimate interest in selecting a method it
regards as “preserving the dignity of the procedure”); id.,
at 66 (ALITO, J., concurring) (a State isn’t required to
modify its protocol in ways that would require the in-
volvement of “persons whose professional ethics rules or
traditions impede their participation”).
   As we’ve seen, two Members of the Court whose votes
were essential to the judgment in Glossip argued that
establishing cruelty consistent with the Eighth Amend-
ment’s original meaning demands slightly more than the
majority opinion there (or the Baze plurality opinion it
followed) suggested. Instead of requiring an inmate to
establish that a State has unreasonably refused to alter its
method of execution to avoid a risk of unnecessary pain,
JUSTICE THOMAS and Justice Scalia contended that an
inmate must show that the State intended its method to
inflict such pain. See Glossip, 576 U. S., at ___ (THOMAS,
J., concurring) (slip op., at 1); Baze, 553 U. S., at 94–107
(THOMAS, J., concurring in judgment). But revisiting that
debate isn’t necessary here because, as we’ll see, the State
was entitled to summary judgment in this case even under
the more forgiving Baze-Glossip test. See Part III, infra.
                             B
  Before turning to the application of Baze and Glossip,
however, we must confront Mr. Bucklew’s argument that a
different standard entirely should govern as-applied chal-
                 Cite as: 587 U. S. ____ (2019)           15

                     Opinion of the Court

lenges like his. He admits that Baze and Glossip supply
the controlling test in facial challenges to a State’s chosen
method of execution. But he suggests that he should not
have to prove an alternative method of execution in his as-
applied challenge because “certain categories” of punish-
ment are “manifestly cruel . . . without reference to any
alternative methods.” Brief for Petitioner 41–42 (internal
quotation marks omitted). He points to “ ‘burning at the
stake, crucifixion, [and] breaking on the wheel’ ” as exam-
ples of “categorically” cruel methods. Ibid. And, he says,
we should use this case to add to the list of “categorically”
cruel methods any method that, as applied to a particular
inmate, will pose a “substantial and particular risk of
grave suffering” due to the inmate’s “unique medical
condition.” Id., at 44.
  The first problem with this argument is that it’s fore-
closed by precedent. Glossip expressly held that identify-
ing an available alternative is “a requirement of all Eighth
Amendment method-of-execution claims” alleging cruel
pain. 576 U. S., at ___ (slip op., at 1) (emphasis added).
And just as binding as this holding is the reasoning under-
lying it. Distinguishing between constitutionally permis-
sible and impermissible degrees of pain, Baze and Glossip
explained, is a necessarily comparative exercise. To decide
whether the State has cruelly “superadded” pain to the
punishment of death isn’t something that can be accom-
plished by examining the State’s proposed method in a
vacuum, but only by “compar[ing]” that method with a
viable alternative. Glossip, 576 U. S., at ___ (slip op., at
13); see Baze, 553 U. S., at 61. As Mr. Bucklew acknowl-
edges when speaking of facial challenges, this comparison
“provides the needed metric” to measure whether the
State is lawfully carrying out an execution or inflicting
“gratuitous” pain. Brief for Petitioner 42–43. Yet it is
that very comparison and needed metric Mr. Bucklew
would now have us discard. Nor does he offer some per-
16                BUCKLEW v. PRECYTHE

                     Opinion of the Court

suasive reason for overturning our precedent. To the
contrary, Mr. Bucklew simply repeats the same argument
the principal dissent offered and the Court expressly and
thoughtfully rejected in Glossip. Just as Mr. Bucklew
argues here, the dissent there argued that “certain meth-
ods of execution” like “burning at the stake” should be
declared “categorically off-limits.” And just as Mr. Buck-
lew submits here, the dissent there argued that any other
“intolerably painful” method of execution should be added
to this list. 576 U. S., at ___–___ (SOTOMAYOR, J., dissent-
ing) (slip op., at 23–24). Mr. Bucklew’s submission, thus,
amounts to no more than a headlong attack on precedent.
  Mr. Bucklew’s argument fails for another independent
reason: It is inconsistent with the original and historical
understanding of the Eighth Amendment on which Baze
and Glossip rest. As we’ve seen, when it comes to deter-
mining whether a punishment is unconstitutionally cruel
because of the pain involved, the law has always asked
whether the punishment “superadds” pain well beyond
what’s needed to effectuate a death sentence. And an-
swering that question has always involved a comparison
with available alternatives, not some abstract exercise in
“categorical” classification. At common law, the ancient
and barbaric methods of execution Mr. Bucklew cites were
understood to be cruel precisely because—by comparison
to other available methods—they went so far beyond what
was needed to carry out a death sentence that they could
only be explained as reflecting the infliction of pain for
pain’s sake. Meanwhile, hanging carried with it an
acknowledged and substantial risk of pain but was not
considered cruel because that risk was thought—by com-
parison to other known methods—to involve no more pain
than was reasonably necessary to impose a lawful death
sentence. See supra, at 9–12.
  What does the principal dissent have to say about all
this? It acknowledges that Glossip’s comparative re-
                 Cite as: 587 U. S. ____ (2019)          17

                     Opinion of the Court

quirement helps prevent facial method-of-execution claims
from becoming a “backdoor means to abolish” the death
penalty. Post, at 8 (opinion of BREYER, J.). But, the dis-
sent assures us, there’s no reason to worry that as-applied
method-of-execution challenges might be used that way.
This assurance misses the point. As we’ve explained, the
alternative-method requirement is compelled by our un-
derstanding of the Constitution, not by mere policy
concerns.
  With that, the dissent is left only to rehash the same
argument that Mr. Bucklew offers. The dissent insists
that some forms of execution are just categorically cruel.
Post, at 10–11. At first and like others who have made
this argument, the dissent offers little more than intuition
to support its conclusion. Ultimately, though, even it bows
to the necessity of something firmer. If a “comparator is
needed” to assess whether an execution is cruel, the dis-
sent tells us, we should compare the pain likely to follow
from the use of a lethal injection in this case with the
pain-free use of lethal injections in mine-run cases. Post,
at 10. But that’s just another way of saying executions
must always be carried out painlessly because they can be
carried out painlessly most of the time, a standard the
Constitution has never required and this Court has re-
jected time and time again. Supra, at 12. To determine
whether the State is cruelly superadding pain, our prece-
dents and history require asking whether the State had
some other feasible and readily available method to carry
out its lawful sentence that would have significantly re-
duced a substantial risk of pain.
  That Mr. Bucklew and the dissent fail to respect the
force of our precedents—or to grapple with the under-
standing of the Constitution on which our precedents
rest—is more than enough reason to reject their view that
as-applied and facial challenges should be treated differ-
ently. But it turns out their position on this score suffers
18                 BUCKLEW v. PRECYTHE

                      Opinion of the Court

from further problems too—problems that neither Mr.
Bucklew nor the dissent even attempts to address.
   Take this one. A facial challenge is really just a claim
that the law or policy at issue is unconstitutional in all its
applications. So classifying a lawsuit as facial or as-
applied affects the extent to which the invalidity of the
challenged law must be demonstrated and the correspond-
ing “breadth of the remedy,” but it does not speak at all to
the substantive rule of law necessary to establish a consti-
tutional violation. Citizens United v. Federal Election
Comm’n, 558 U. S. 310, 331 (2010). Surely it would be
strange for the same words of the Constitution to bear
entirely different meanings depending only on how broad
a remedy the plaintiff chooses to seek. See Gross v. United
States, 771 F. 3d 10, 14–15 (CADC 2014) (“ ‘[T]he substan-
tive rule of law is the same for both [facial and as-applied]
challenges’ ”); Brooklyn Legal Servs. Corp. v. Legal Servs.
Corp., 462 F. 3d 219, 228 (CA2 2006) (the facial/as-applied
distinction affects “the extent to which the invalidity of a
statute need be demonstrated,” not “the substantive rule of
law to be used”). And surely, too, it must count for some-
thing that we have found not a single court decision in
over 200 years suggesting that the Eighth Amendment’s
meaning shifts in this way. To the contrary, our precedent
suggests just the opposite. In the related context of an
Eighth Amendment challenge to conditions of confine-
ment, we have seen “no basis whatever” for applying a
different legal standard to “deprivations inflicted upon all
prisoners” and those “inflicted upon particular prisoners.”
Wilson v. Seiter, 501 U. S. 294, 299, n. 1 (1991).
   Here’s yet another problem with Mr. Bucklew’s argu-
ment: It invites pleading games. The line between facial
and as-applied challenges can sometimes prove “amor-
phous,” Elgin v. Department of Treasury, 567 U. S. 1, 15
(2012), and “not so well defined,” Citizens United, 558
U. S., at 331. Consider an example. Suppose an inmate
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                      Opinion of the Court

claims that the State’s lethal injection protocol violates the
Eighth Amendment when used to execute anyone with a
very common but not quite universal health condition.
Should such a claim be regarded as facial or as-applied?
In another context, we sidestepped a debate over how to
categorize a comparable claim—one that neither sought
“to strike [the challenged law] in all its applications” nor
was “limited to plaintiff ’s particular case”—by concluding
that “[t]he label is not what matters.” Doe v. Reed, 561
U. S. 186, 194 (2010). To hold now, for the first time, that
choosing a label changes the meaning of the Constitution
would only guarantee a good deal of litigation over labels,
with lawyers on each side seeking to classify cases to
maximize their tactical advantage. Unless increasing the
delay and cost involved in carrying out executions is the
point of the exercise, it’s hard to see the benefit in placing
so much weight on what can be an abstruse exercise.
  Finally, the burden Mr. Bucklew must shoulder under
the Baze-Glossip test can be overstated. An inmate seek-
ing to identify an alternative method of execution is not
limited to choosing among those presently authorized by a
particular State’s law.         Missouri itself seemed to
acknowledge as much at oral argument. Tr. of Oral Arg.
65. So, for example, a prisoner may point to a well-
established protocol in another State as a potentially
viable option. Of course, in a case like that a court would
have to inquire into the possibility that one State pos-
sessed a legitimate reason for declining to adopt the proto-
col of another. See supra, at 13–14. And existing state
law might be relevant to determining the proper proce-
dural vehicle for the inmate’s claim.           See Hill v.
McDonough, 547 U. S. 573, 582–583 (2006) (if the relief
sought in a 42 U. S. C. §1983 action would “foreclose the
State from implementing the [inmate’s] sentence under
present law,” then “recharacterizing a complaint as an
action for habeas corpus might be proper”). But the
20                 BUCKLEW v. PRECYTHE

                     Opinion of the Court

Eighth Amendment is the supreme law of the land, and
the comparative assessment it requires can’t be controlled
by the State’s choice of which methods to authorize in its
statutes. In light of this, we see little likelihood that an
inmate facing a serious risk of pain will be unable to iden-
tify an available alternative—assuming, of course, that
the inmate is more interested in avoiding unnecessary
pain than in delaying his execution.
                            III
   Having (re)confirmed that anyone bringing a method of
execution claim alleging the infliction of unconstitution-
ally cruel pain must meet the Baze-Glossip test, we can now
turn to the question whether Mr. Bucklew is able to sat-
isfy that test. Has he identified a feasible and readily im-
plemented alternative method of execution the State
refused to adopt without a legitimate reason, even though
it would significantly reduce a substantial risk of severe
pain? Because the case comes to us after the entry of
summary judgment, this appeal turns on whether Mr.
Bucklew has shown a genuine issue of material fact war-
ranting a trial.
                             A
  We begin with the question of a proposed alternative
method. Through much of this case and despite many
opportunities, Mr. Bucklew refused to identify any alter-
native method of execution, choosing instead to stand on
his argument that Baze and Glossip’s legal standard
doesn’t govern as-applied challenges like his (even after
the Eighth Circuit rejected that argument). Only when
the district court warned that his continued refusal to
abide this Court’s precedents would result in immediate
dismissal did Mr. Bucklew finally point to nitrogen hy-
poxia. The district court then afforded Mr. Bucklew “exten-
sive discovery” to explore the viability of that alternative.
                 Cite as: 587 U. S. ____ (2019)           21

                     Opinion of the Court

883 F. 3d, at 1094. But even after all that, we conclude
Mr. Bucklew has failed for two independent reasons to
present a triable question on the viability of nitrogen
hypoxia as an alternative to the State’s lethal injection
protocol.
    First, an inmate must show that his proposed alterna-
tive method is not just theoretically “ ‘feasible’ ” but also
“ ‘readily implemented.’ ” Glossip, 576 U. S., at ___–___
(slip op., at 12–13). This means the inmate’s proposal
must be sufficiently detailed to permit a finding that the
State could carry it out “relatively easily and reasonably
quickly.” McGehee v. Hutchinson, 854 F. 3d 488, 493 (CA8
2017); Arthur v. Commissioner, Ala. Dept. of Corrections,
840 F. 3d 1268, 1300 (CA11 2016). Mr. Bucklew’s bare-
bones proposal falls well short of that standard. He has
presented no evidence on essential questions like how
nitrogen gas should be administered (using a gas chamber,
a tent, a hood, a mask, or some other delivery device); in
what concentration (pure nitrogen or some mixture of
gases); how quickly and for how long it should be intro-
duced; or how the State might ensure the safety of the
execution team, including protecting them against the risk
of gas leaks. Instead of presenting the State with a read-
ily implemented alternative method, Mr. Bucklew (and the
principal dissent) point to reports from correctional au-
thorities in other States indicating that additional study is
needed to develop a protocol for execution by nitrogen
hypoxia. See App. 697 (Oklahoma grand jury report rec-
ommending that the State “retain experts” and conduct
“further research” to “determine how to carry out the
sentence of death by this method”); id., at 736 (report of
Louisiana Dept. of Public Safety & Corrections stating
that “[r]esearch . . . is ongoing” to develop a nitrogen hy-
poxia protocol). That is a proposal for more research, not
the readily implemented alternative that Baze and Glossip
require.
22                     BUCKLEW v. PRECYTHE

                          Opinion of the Court

  Second, and relatedly, the State had a “legitimate”
reason for declining to switch from its current method of
execution as a matter of law. Baze, 553 U. S., at 52.
Rather than point to a proven alternative method, Mr.
Bucklew sought the adoption of an entirely new method—
one that had “never been used to carry out an execution”
and had “no track record of successful use.” McGehee, 854
F. 3d, at 493. But choosing not to be the first to experi-
ment with a new method of execution is a legitimate rea-
son to reject it. In Baze we observed that “no other State
ha[d] adopted” the one-drug protocol the inmates sought
and they had “proffered no study showing” their one-drug
protocol would be as effective and humane as the State’s
existing three-drug protocol. 553 U. S., at 57. Under
those circumstances, we held as a matter of law that
Kentucky’s refusal to adopt the inmates’ proffered protocol
could not “constitute a violation of the Eighth Amend-
ment.” Ibid. The Eighth Amendment prohibits States
from dredging up archaic cruel punishments or perhaps
inventing new ones, but it does not compel a State to
adopt “untried and untested” (and thus unusual in the
constitutional sense) methods of execution. Id., at 41.1

——————
  1 While   this case has been pending, a few States have authorized
nitrogen hypoxia as a method of execution. See 2018 Ala. Acts no.
2018–353 (allowing condemned inmates to elect execution by nitrogen
hypoxia); 2017 Miss. Laws ch. 406, p. 905 (authorizing execution by
nitrogen hypoxia only if lethal injection is held unconstitutional or is
otherwise unavailable); 2015 Okla. Sess. Laws ch. 75, p. 244 (same). In
March 2018, officials in Oklahoma announced that, due to the unavail-
ability of lethal injection drugs, the State would use nitrogen gas for its
executions going forward. See Williams, Oklahoma Proposes To Use
Nitrogen Gas for Executions by Asphyxiation, N. Y. Times, Mar. 15,
2018, p. A22. But Oklahoma has so far been unable to find a manufac-
turer willing to sell it a gas delivery device for use in executions. See
Clay, State Not Ready for Executions, The Oklahoman, Jan. 27, 2019,
p. A1. To date, no one in this case has pointed us to an execution in
this country using nitrogen gas.
                  Cite as: 587 U. S. ____ (2019)           23

                      Opinion of the Court

                               B
  Even if a prisoner can carry his burden of showing a
readily available alternative, he must still show that it
would significantly reduce a substantial risk of severe
pain. Glossip, 576 U. S., at ___ (slip op., at 13); Baze, 553
U. S., at 52. A minor reduction in risk is insufficient; the
difference must be clear and considerable. Over the
course of this litigation, Mr. Bucklew’s explanation why
nitrogen hypoxia meets this standard has evolved signifi-
cantly. But neither of the two theories he has advanced in
this Court turns out to be supported by record evidence.
  First, Mr. Bucklew points to several risks that he alleges
could result from use of the State’s lethal injection protocol
that would not be present if the State used nitrogen gas.
For example, he says the execution team might try to insert
an IV into one of his peripheral veins, which could cause
the vein to rupture; or the team might instead use an
allegedly painful “cut-down” procedure to access his femo-
ral vein. He also says that he might be forced to lie flat on
his back during the execution, which could impair his
breathing even before the pentobarbital is administered.
And he says the stress from all this could cause his tumors
to bleed, further impairing his breathing. These risks, we
may assume, would not exist if Mr. Bucklew were exe-
cuted by his preferred method of nitrogen hypoxia.
  The problem with all of these contentions is that they
rest on speculation unsupported, if not affirmatively con-
tradicted, by the evidence in this case. Nor does the prin-
cipal dissent contend otherwise. So, for example, uncon-
troverted record evidence indicates that the execution
team will have discretion to adjust the gurney to whatever
position is in Mr. Bucklew’s best medical interests. 883
F. 3d, at 1092, n. 3; App. 531. Moreover, the State agreed
in the district court that it would not try to place an IV in
Mr. Bucklew’s compromised peripheral veins. Id., at 820;
see Brief for Appellant in No. 17–3052 (CA8), p. 7. And,
24                    BUCKLEW v. PRECYTHE

                         Opinion of the Court

assuming without granting that using a cut-down would
raise issues under the Eighth Amendment—but see Noon-
er v. Norris, 594 F. 3d 592, 604 (CA8 2010) (holding oth-
erwise)—the State’s expert, Dr. Michael Antognini, testi-
fied without contradiction that it should be possible to
place an IV in Mr. Bucklew’s femoral vein without using a
cut-down procedure, App. 350. Mr. Bucklew responds by
pointing to the warden’s testimony that he once saw medi-
cal staff perform a cut-down as part of an execution; but
there’s no evidence that what the warden saw was an
attempt to access a femoral vein, as opposed to some other
vein.
   Moreover, to the extent the record is unclear on any of
these issues, Mr. Bucklew had ample opportunity to con-
duct discovery and develop a factual record concerning
exactly what procedures the State planned to use. He
failed to do so—presumably because the thrust of his
constitutional claim was that any attempt to execute him
via lethal injection would be unconstitutional, regardless
of the specific procedures the State might use. As the
court of appeals explained: “Having taken the position
that any lethal injection procedure would violate the
Eighth Amendment,” Mr. Bucklew “made no effort to
determine what changes, if any, the [State] would make in
applying its lethal injection protocol” to him, and he “never
urged the district court to establish a suitable fact-finding
procedure . . . to define the as-applied lethal injection
protocol [the State] intends to use.” 883 F. 3d, at 1095–
1096.2
——————
  2 While the district court allowed discovery on many other matters,

Mr. Bucklew protests that it did not permit him to learn the identities
of the lethal injection execution team members, to depose them, or to
inquire into their qualifications, training, and experience. Like the
Eighth Circuit, we see no abuse of discretion in the district court’s
discovery rulings. As the district court explained, Mr. Bucklew argues
that there is no way he may be constitutionally executed by lethal
                     Cite as: 587 U. S. ____ (2019)                   25

                          Opinion of the Court

   Second, Mr. Bucklew contends that the lethal injection
itself will expose him to a substantial risk of severe pain
that could be eliminated by adopting his preferred method.
He claims that once the sedative pentobarbital is injected
he will “lose the ability to manage” the tumors in his
airway and, as a result, will experience a “sense of suffoca-
tion” for some period of time before the State’s sedative
renders him fully unconscious. Brief for Petitioner 12–13.
“It is during this in-between twilight stage,” according to
his expert, Dr. Zivot, “that Mr. Bucklew is likely to experi-
ence prolonged feelings of suffocation and excruciating
pain.” App. 234. Mr. Bucklew admits that similar feelings
of suffocation could occur with nitrogen, the only differ-
ence being the potential duration of the so-called “twilight
stage.” He contends that with nitrogen the stage would
last at most 20 to 30 seconds, while with pentobarbital it
could last up to several minutes.
   But here again the record contains insufficient evidence
to permit Mr. Bucklew to avoid summary judgment. For
starters, in the courts below Mr. Bucklew maintained he
would have trouble managing his airway only if he were
forced to lie supine, which (as we’ve explained) the evi-
dence shows he won’t be. (The dissenters don’t address
this point.) But even indulging his new claim that he will
have this difficulty regardless of position, he still has
failed to present colorable evidence that nitrogen would
significantly reduce his risk of pain. We can assume for
argument’s sake that Mr. Bucklew is correct that with
nitrogen the twilight stage would last 20 to 30 seconds.
The critical question, then, is how long that period might
last with pentobarbital. The State’s expert, Dr. Antognini,
testified that pentobarbital, too, would render Mr. Buck-
——————
injection, even with modifications to the State’s lethal injection proto-
col. And in a case like that, discovery into such granular matters as
who administers the protocol simply is not relevant.
26                 BUCKLEW v. PRECYTHE

                     Opinion of the Court

lew fully unconscious and incapable of experiencing pain
within 20 to 30 seconds. Id., at 299–301, 432–433. Dr.
Zivot disagreed; but when he was asked how long he
thought the twilight stage would last with pentobarbital,
his testimony was evasive. Eventually, he said his “num-
ber would be longer than” 20 to 30 seconds, but he de-
clined to say how much longer. Id., at 195. Instead, he
referenced a 2015 study on euthanasia in horses. He said
the study found that when horses were given a large dose
of pentobarbital (along with other drugs), they exhibited
“isoelectric EEG”—a complete absence of detectable brain
activity—after 52 to 240 seconds. Id., at 194–196. The
district court assumed Dr. Zivot meant that “pain might
be felt until measurable brain activity ceases” and that,
extrapolating from the horse study, it might take up to
four minutes for pentobarbital to “induc[e] a state in
which [Mr. Bucklew] could no longer sense that he is
choking or unable to breathe.” The district court acknowl-
edged, however, that this might be “a generous interpreta-
tion of Dr. Zivot’s testimony.” Id., at 822, and n. 5.
   In fact, there’s nothing in the record to suggest that Mr.
Bucklew will be capable of experiencing pain for signifi-
cantly more than 20 to 30 seconds after being injected
with pentobarbital. For one thing, Mr. Bucklew’s lawyer
now admits that Dr. Zivot “crossed up the numbers” from
the horse study. Tr. of Oral Arg. 7–8, 11–12. The study
actually reported that the horses displayed isoelectric
EEG between 2 and 52 seconds after infusion of pentobar-
bital was completed, with an average time of less than 24
seconds. App. 267. So if anything, the horse study ap-
pears to bolster Dr. Antognini’s time estimate. For another
thing, everyone now also seems to acknowledge that
isoelectric EEG is the wrong measure. Dr. Zivot never
claimed the horses were capable of experiencing pain until
they reached isoelectric EEG. And Mr. Bucklew’s lawyer
now concedes that doctors perform major surgery on hu-
                  Cite as: 587 U. S. ____ (2019)           27

                      Opinion of the Court

man patients with measurable EEG readings, which
strongly suggests that Mr. Bucklew will be insensible to
pain before reaching isoelectric EEG. Tr. of Oral Arg. 9.
Finally, the record evidence even allows the possibility
that nitrogen could increase the risk of pain. Because Dr.
Zivot declined to testify about the likely effects of nitrogen
gas, Mr. Bucklew must rely on Dr. Antognini’s testimony.
And while Dr. Antognini did say he thought nitrogen’s
“onset of action” could be “relatively fast,” App. 458, he
added that the effects of nitrogen could vary depending on
exactly how it would be administered—information Mr.
Bucklew hadn’t provided. Indeed, he stated that “depend-
ing on . . . how it’s used, you might get more suffering from
nitrogen gas than you would have” from the State’s cur-
rent protocol. Id., at 460–461.
  Of course, the principal dissent maintains that Dr.
Zivot’s testimony supports an inference that pentobarbital
might cause Mr. Bucklew to suffer for a prolonged period.
But its argument rests on a number of mistakes about the
record. For example, the dissent points to Dr. Zivot’s
remark that, with pentobarbital, “ ‘the period of time
between receiving the injection and death could range over
a few minutes to many minutes.’ ” Post, at 4, 6 (quoting
App. 222). From this, the dissent concludes that Mr.
Bucklew may suffer for “up to several minutes.” Post, at 1,
6, 9. But everyone agrees that the relevant question isn’t
how long it will take for Mr. Bucklew to die, but how long
he will be capable of feeling pain. Seeking to address the
problem, the dissent next points to another part of Dr.
Zivot’s testimony and says it means Mr. Bucklew could
experience pain during the entire time between injection
and death. Post, at 6, 13 (quoting App. 222). But the
dissent clips the relevant quotation. As the full quotation
makes clear, Dr. Zivot claimed that Mr. Bucklew might be
unable to “maintain the integrity of his airway” until he
died—but he carefully avoided claiming that Mr. Bucklew
28                    BUCKLEW v. PRECYTHE

                          Opinion of the Court

would be capable of feeling pain until he died.3 To avoid
this problem, the dissent quotes Dr. Zivot’s assertions that
pentobarbital might not produce “ ‘rapid unconsciousness’ ”
and that Mr. Bucklew’s suffering with pentobarbital could
be “ ‘prolonged.’ ” Post, at 4–6, 13 (quoting App. 233–234).
But Dr. Zivot’s statements here, too, fail to specify how
long Mr. Bucklew is likely to be able to feel pain. The
hard fact is that, when Dr. Zivot was finally compelled to
offer a view on this question, his only response was to
refer to the horse study. Id., at 195–196. The dissent’s
effort to suggest that Dr. Zivot “did not rely exclusively or
even heavily on that study,” post, at 7, is belied by (among
other things) Mr. Bucklew’s own brief in this Court, which
asserted that the twilight stage during which he might
feel pain could last “between 52 and 240 seconds,” based
entirely on a citation of Dr. Zivot’s incorrect testimony
about the horse study. Brief for Petitioner 13.
   In sum, even if execution by nitrogen hypoxia were a
feasible and readily implemented alternative to the State’s
chosen method, Mr. Bucklew has still failed to present any
evidence suggesting that it would significantly reduce his
risk of pain. For that reason as well, the State was enti-
tled to summary judgment on Mr. Bucklew’s Eighth
Amendment claim.4
——————
  3 Here’s the full quotation, with the portion quoted by the dissent

underlined:
     “As a result of his inability to maintain the integrity of his airway
     for the period of time beginning with the injection of the Pento-
     barbital solution and ending with Mr. Bucklew’s death several
     minutes to as long as many minutes later, Mr. Bucklew would be
     highly likely to experience feelings of ‘air hunger’ and the excruci-
     ating pain of prolonged suffocation resulting from the complete
     obstruction of his airway by the large vascular tumor.” App. 222.
  4 The State contends that Mr. Bucklew’s claim should fail for yet an-

other reason: because, in the State’s view, the evidence does not show
that he is very likely to suffer “ ‘severe pain’ ” cognizable under the
                    Cite as: 587 U. S. ____ (2019)                  29

                         Opinion of the Court

                               IV
  “Both the State and the victims of crime have an im-
portant interest in the timely enforcement of a sentence.”
Hill, 547 U. S., at 584. Those interests have been frus-
trated in this case. Mr. Bucklew committed his crimes
more than two decades ago. He exhausted his appeal and
separate state and federal habeas challenges more than a
decade ago. Yet since then he has managed to secure
delay through lawsuit after lawsuit. He filed his current
challenge just days before his scheduled execution. That
suit has now carried on for five years and yielded two
appeals to the Eighth Circuit, two 11th-hour stays of
execution, and plenary consideration in this Court. And
despite all this, his suit in the end amounts to little more
than an attack on settled precedent, lacking enough evi-
dence even to survive summary judgment—and on not just
one but many essential legal elements set forth in our case
law and required by the Constitution’s original meaning.
  The people of Missouri, the surviving victims of Mr.
Bucklew’s crimes, and others like them deserve better.
Even the principal dissent acknowledges that “the long
delays that now typically occur between the time an of-
fender is sentenced to death and his execution” are “exces-
sive.” Post, at 16. The answer is not, as the dissent incon-
gruously suggests, to reward those who interpose delay
with a decree ending capital punishment by judicial fiat.
Post, at 18. Under our Constitution, the question of capi-
tal punishment belongs to the people and their represent-
atives, not the courts, to resolve. The proper role of courts
is to ensure that method-of-execution challenges to law-
——————
Eighth Amendment. Glossip v. Gross, 576 U. S. ___, ___ (2015) (slip
op., at 13) (quoting Baze v. Rees, 553 U. S. 35, 52 (2008); emphasis
added). We have no need, however, to address that argument because
(as explained above) Mr. Bucklew fails even to show that a feasible and
readily available alternative could significantly reduce the pain he
alleges.
30                     BUCKLEW v. PRECYTHE

                          Opinion of the Court

fully issued sentences are resolved fairly and expeditiously.
Courts should police carefully against attempts to use
such challenges as tools to interpose unjustified delay.
Last-minute stays should be the extreme exception, not
the norm, and “the last-minute nature of an application”
that “could have been brought” earlier, or “an applicant’s
attempt at manipulation,” “may be grounds for denial of a
stay.” Hill, 547 U. S., at 584 (internal quotation marks
omitted). So, for example, we have vacated a stay entered
by a lower court as an abuse of discretion where the in-
mate waited to bring an available claim until just 10 days
before his scheduled execution for a murder he had com-
mitted 24 years earlier. See Dunn v. Ray, 586 U. S. ___
(2019).5 If litigation is allowed to proceed, federal courts
“can and should” protect settled state judgments from
“undue interference” by invoking their “equitable powers”
to dismiss or curtail suits that are pursued in a “dilatory”
——————
   5 Seeking to relitigate Dunn v. Ray, the principal dissent asserts that

that case involved no undue delay because the inmate “brought his
claim only five days after he was notified” that the State would not
allow his spiritual adviser to be present with him in the execution
chamber itself, although it would allow the adviser to be present on the
other side of a glass partition. Post, at 17. But a state statute listed
“[t]he spiritual adviser of the condemned” as one of numerous individ-
uals who would be allowed to “be present at an execution,” many of
whom—such as “newspaper reporters,” “relatives or friends of the
condemned person,” and “the victim’s immediate family members”—
obviously would not be allowed into the chamber itself. Ala. Code §15–
18–83 (2018). The inmate thus had long been on notice that there was
a question whether his adviser would be allowed into the chamber or
required to remain on the other side of the glass. Yet although he had
been on death row since 1999, and the State had set a date for his
execution on November 6, 2018, he waited until January 23, 2019—just
15 days before the execution—to ask for clarification. He then brought
a claim 10 days before the execution and sought an indefinite stay.
This delay implicated the “strong equitable presumption” that no stay
should be granted “where a claim could have been brought at such a
time as to allow consideration of the merits without requiring entry of a
stay.” Hill v. McDonough, 547 U. S. 573, 584 (2006).
                 Cite as: 587 U. S. ____ (2019)          31

                     Opinion of the Court

fashion or based on “speculative” theories. Id., at 584–
585.
                            *
  The judgment of the court of appeals is

                                                  Affirmed.
                  Cite as: 587 U. S. ____ (2019)            1

                     THOMAS, J., concurring

SUPREME COURT OF THE UNITED STATES
                          _________________

                          No. 17–8151
                          _________________


    RUSSELL BUCKLEW, PETITIONER v. ANNE L.
  PRECYTHE, DIRECTOR, MISSOURI DEPARTMENT
            OF CORRECTIONS, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
           APPEALS FOR THE EIGHTH CIRCUIT
                         [April 1, 2019]

  JUSTICE THOMAS, concurring.
  I adhere to my view that “a method of execution violates
the Eighth Amendment only if it is deliberately designed
to inflict pain.” Baze v. Rees, 553 U. S. 35, 94 (2008) (opin-
ion concurring in judgment); ante, at 14. Because there is
no evidence that Missouri designed its protocol to inflict
pain on anyone, let alone Russell Bucklew, I would end the
inquiry there. Nonetheless, I join the Court’s opinion in
full because it correctly explains why Bucklew’s claim fails
even under the Court’s precedents.
  I write separately to explain why JUSTICE BREYER’s
dissenting opinion does not cast doubt on this standard.
Post, at 15–16. As I explained in Baze, “the evil the
Eighth Amendment targets is intentional infliction of
gratuitous pain.” 553 U. S., at 102 (opinion concurring in
judgment). The historical evidence shows that the Fram-
ers sought to disable Congress from imposing various
kinds of torturous punishments, such as “ ‘gibbeting,’ ”
“burning at the stake,” and “ ‘embowelling alive, behead-
ing, and quartering.’ ” Id., at 95–98 (quoting 4 W. Black-
stone, Commentaries *376 (Blackstone), and S. Banner,
The Death Penalty: An American History 71–72 (2002)).
In England, these aggravated forms of capital punishment
were “ ‘superadded’ ” to increase terror and disgrace for
2                  BUCKLEW v. PRECYTHE

                     THOMAS, J., concurring

“ ‘very atrocious crimes,’ ” such as treason and murder.
See Baze, supra, at 96–97 (quoting 4 Blackstone *376).
The founding generation ratified the Eighth Amendment
to reject that practice, contemplating that capital punish-
ment would continue, but without those punishments
deliberately designed to superadd pain. See Baze, 553
U. S., at 97–98. Under this view, the constitutionality of a
particular execution thus turns on whether the Govern-
ment “deliberately designed” the method of execution “to
inflict pain,” id., at 94, without regard to the subjective
intent of the executioner.
    Contrary to JUSTICE BREYER’s suggestion, my view does
not render the Eighth Amendment “a static prohibition”
proscribing only “the same things that it proscribed in the
18th century.” Post, at 15–16. A method of execution not
specifically contemplated at the founding could today be
imposed to “superad[d]” “terror, pain, or disgrace.” 4
Blackstone *376. Thankfully—and consistent with Justice
Story’s view that the Eighth Amendment is “wholly un-
necessary in a free government,” 3 J. Story, Commentaries
on the Constitution of the United States 750 (1833)—
States do not attempt to devise such diabolical punish-
ments. E.g., Baze, supra, at 107 (“Kentucky adopted its
lethal injection protocol in an effort to make capital pun-
ishment more humane”). It is therefore unsurprising that,
despite JUSTICE BREYER’s qualms about the death pen-
alty, e.g., post, at 18, this Court has never held a method of
execution unconstitutional. Because the Court correctly
declines to do so again today, I join in full.
                 Cite as: 587 U. S. ____ (2019)           1

                  KAVANAUGH, J., concurring

SUPREME COURT OF THE UNITED STATES
                         _________________

                         No. 17–8151
                         _________________


   RUSSELL BUCKLEW, PETITIONER v. ANNE L.
 PRECYTHE, DIRECTOR, MISSOURI DEPARTMENT
           OF CORRECTIONS, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
           APPEALS FOR THE EIGHTH CIRCUIT
                        [April 1, 2019]

   JUSTICE KAVANAUGH, concurring.
   When an inmate raises an as-applied constitutional
challenge to a particular method of execution—that is, a
challenge to a method of execution that is constitutional in
general but that the inmate says is very likely to cause
him severe pain—one question is whether the inmate
must identify an available alternative method of execution
that would significantly reduce the risk of severe pain.
Applying our recent decisions in Glossip v. Gross, 576
U. S. ___ (2015), and Baze v. Rees, 553 U. S. 35 (2008)
(plurality opinion), the Court’s answer to that question is
yes. Under those precedents, I agree with the Court’s
holding and join the Court’s opinion.
   I write to underscore the Court’s additional holding that
the alternative method of execution need not be author-
ized under current state law—a legal issue that had been
uncertain before today’s decision. See Arthur v. Dunn, 580
U. S. ___, ___–___ (2017) (slip op., at 9–11) (SOTOMAYOR,
J., dissenting from denial of certiorari). Importantly, all
nine Justices today agree on that point. Ante, at 19; post,
at 14 (BREYER, J., dissenting).
   As the Court notes, it follows from that additional hold-
ing that the burden of the alternative-method requirement
“can be overstated.” Ante, at 19. Indeed,      the    Court
2                  BUCKLEW v. PRECYTHE

                   KAVANAUGH, J., concurring

states: “[W]e see little likelihood that an inmate facing a
serious risk of pain will be unable to identify an available
alternative.” Ante, at 20.
   In other words, an inmate who contends that a particu-
lar method of execution is very likely to cause him severe
pain should ordinarily be able to plead some alternative
method of execution that would significantly reduce the
risk of severe pain. At oral argument in this Court, the
State suggested that the firing squad would be such an
available alternative, if adequately pleaded. Tr. of Oral
Arg. 63–64 (“He can plead firing squad. . . . Of course, if he
had . . . pleaded firing squad, it’s possible that Missouri
could have executed him by firing squad”). JUSTICE
SOTOMAYOR has likewise explained that the firing squad
is an alternative method of execution that generally causes
an immediate and certain death, with close to zero risk
of a botched execution. See Arthur, 580 U. S., at ___–___
(slip op., at 17–18). I do not here prejudge the question
whether the firing squad, or any other alternative method
of execution, would be a feasible and readily implemented
alternative for every State. See McGehee v. Hutchinson,
854 F. 3d 488, 493–494 (CA8 2017). Rather, I simply
emphasize the Court’s statement that “we see little likeli-
hood that an inmate facing a serious risk of pain will be
unable to identify an available alternative.” Ante, at 20.
                 Cite as: 587 U. S. ____ (2019)           1

                    BREYER, J., dissenting

SUPREME COURT OF THE UNITED STATES
                         _________________

                         No. 17–8151
                         _________________


   RUSSELL BUCKLEW, PETITIONER v. ANNE L.
 PRECYTHE, DIRECTOR, MISSOURI DEPARTMENT
           OF CORRECTIONS, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
           APPEALS FOR THE EIGHTH CIRCUIT
                        [April 1, 2019]

   JUSTICE BREYER, with whom JUSTICE GINSBURG,
JUSTICE SOTOMAYOR, and JUSTICE KAGAN join as to all
but Part III, dissenting.
   The Court’s decision in this case raises three questions.
The first is primarily a factual question, namely, whether
Bucklew has established genuine issues of material fact
concerning whether executing him by lethal injection
would cause him excessive suffering. The second is pri-
marily a legal question, namely, whether a prisoner like
Bucklew with a rare medical condition must identify an
alternative method by which the State may execute him.
And the third is a more general question, namely, how to
minimize delays in executing offenders who have been
condemned to death.
   I disagree with the majority’s answers to all three ques-
tions. Bucklew cites evidence that executing him by lethal
injection will cause the tumors that grow in his throat to
rupture during his execution, causing him to sputter,
choke, and suffocate on his own blood for up to several
minutes before he dies. That evidence establishes at this
stage of the proceedings that executing Bucklew by lethal
injection risks subjecting him to constitutionally imper-
missible suffering. The majority holds that the State may
execute him anyway. In my view, that holding violates
2                  BUCKLEW v. PRECYTHE

                     BREYER, J., dissenting

the clear command of the Eighth Amendment.
                               I
   I begin with a factual question: whether Bucklew has
established that, because of his rare medical condition, the
State’s current method of execution risks subjecting him to
excessive suffering. See Glossip v. Gross, 576 U. S. ___,
___ (2015) (slip op., at 13) (requiring “a demonstrated risk
of severe pain”); see also Baze v. Rees, 553 U. S. 35, 50
(2008) (plurality opinion) (requiring “a substantial risk of
serious harm” (internal quotation marks omitted)).
   There is no dispute as to the applicable summary judg-
ment standard. Because the State moved for summary
judgment, it can prevail if, but only if, it “shows that there
is no genuine dispute as to any material fact.” Fed. Rule
Civ. Proc. 56(a); see also Anderson v. Liberty Lobby, Inc.,
477 U. S. 242, 248 (1986). On review, we examine the
record as a whole, which includes “depositions, documents,
[and] affidavits or declarations.” Rule 56(c). And we must
construe the evidence in the light most favorable to Buck-
lew and draw every justifiable inference in his favor. See
Tolan v. Cotton, 572 U. S. 650, 651 (2014) (per curiam).
                             A
   Bucklew has easily established a genuine issue of mate-
rial fact regarding whether an execution by lethal injec-
tion would subject him to impermissible suffering.
   The record indicates that Bucklew suffers from a con-
genital condition known as cavernous hemangioma that
causes tumors filled with blood vessels to grow throughout
his body, including in his head, face, neck, and oral cavity.
The condition is rare. One study estimates that hemangi-
omas in the oral cavity occur in less than one percent of
the population, and that hemangiomas like Bucklew’s
have been identified in five cases. See Wang, Chen, Mo-
jica, & Chen, Cavernous Hemangioma of the Uvula, 8 N.
                 Cite as: 587 U. S. ____ (2019)           3

                    BREYER, J., dissenting

Am. J. Med. & Sci. 56, 56–59 (2015).
   Tumors grow out of Bucklew’s lip and over his mouth, as
well as on his hard and soft palates. One tumor also
grows directly on Bucklew’s uvula, which has become
“grossly enlarged” as a result. App. 225. (The uvula is the
“pendent fleshy lobe” that hangs from the back of the
throat. Merriam-Webster’s Collegiate Dictionary 1379
(11th ed. 2003).) Bucklew’s tumors obstruct his airway
and make it difficult for him to breathe. His difficulty
breathing is chronic, but is particularly acute when he lies
flat and gravity pulls his engorged uvula into his airway.
He often has to adjust the positioning of his head to pre-
vent his uvula from obstructing his breathing. He sleeps
at a 45-degree angle to facilitate breathing, and he often
wakes up in the middle of the night gasping for air.
   Due to the sensitivity of his tumors, even minimal con-
tact may cause them to hemorrhage. He has described
past hemorrhages as “ ‘squirting’ ” or “leaking” blood, and
he states that the first thing he does each morning is to
wipe the blood off his face that leaked from his nose and
mouth as he slept. Bucklew’s condition is progressive and,
due to the risk of significant blood loss caused by the
sensitivity of his tumors, cannot be treated by surgery.
   Bucklew maintains that, as a result of this medical
condition, executing him by lethal injection would prove
excruciatingly painful. In support of this claim, Bucklew
submitted sworn declarations and deposition testimony
from an expert witness, Dr. Joel Zivot, an anesthesiologist.
Dr. Zivot provided extensive testimony regarding the pain
that Bucklew would likely endure in an execution by
lethal injection:

  Dr. Zivot testified that in light of “the degree to which
   Mr. Bucklew’s airway is compromised by the hemangi-
   omas” and “the particular psychological and physical
   effects of lethal injection, it is highly likely that Mr.
4                    BUCKLEW v. PRECYTHE

                       BREYER, J., dissenting

     Bucklew would be unable to maintain the integrity of
     his airway during the time after receiving the lethal
     injection and before death.” App. 221.

     Dr. Zivot explained that, as a result of “the highly fri-
      able and fragile state of the tissue of Mr. Bucklew’s
      mouth and airway,” Bucklew “will likely experience
      hemorrhaging and/or the possible rupture of the tu-
      mor” on his uvula during his execution. Id., at 222.

     Dr. Zivot added that the “hemorrhaging will further
      impede Mr. Bucklew’s airway by filling his mouth and
      airway with blood, causing him to choke and cough on
      his own blood.” Ibid.

     Dr. Zivot concluded that “it is highly likely that Mr.
      Bucklew, given his specific congenital medical condi-
      tion, cannot undergo lethal injection without experi-
      encing the excruciating pain and suffering” of “suffoca-
      tion, convulsions, and visible hemorrhaging.” Id.,
      at 223.

  Dr. Zivot also testified about the duration of pain to
which an execution by lethal injection would subject Buck-
lew, describing it as “prolonged.” Id., at 234.

     Dr. Zivot stated that the effects of a pentobarbital in-
      jection “are highly unlikely to be instantaneous and
      the period of time between receiving the injection and
      death could range over a few minutes to many
      minutes.” Id., at 222 (emphasis added).

     Dr. Zivot “strongly disagree[d] with [the State’s ex-
      pert’s] repeated claim that the pentobarbital injection
      would result in ‘rapid unconsciousness.’ ” Id., at 233.
                  Cite as: 587 U. S. ____ (2019)            5

                     BREYER, J., dissenting

  Dr. Zivot explained that Bucklew “would likely experi-
   ence unconsciousness that sets in progressively as the
   chemical circulates through his system” and that it
   was during this period that Bucklew was “likely to ex-
   perience prolonged feelings of suffocation and excruci-
   ating pain.” Id., at 233–234.

  The State asked the District Court to grant summary
judgment in its favor on the theory that Bucklew failed to
identify a genuine factual issue regarding whether an
execution by lethal injection would be impermissibly
painful. The District Court refused. The court believed
that Bucklew had adequately shown that for up to several
minutes he “could be aware that he is choking or unable to
breathe but be unable to ‘adjust’ his breathing to remedy
the situation.” Id., at 827. Recognizing that the State’s
evidence suggested that Bucklew would experience this
choking sensation for a shorter period, the District Court
concluded that the dispute between the experts was “a
factual dispute that the Court cannot resolve on summary
judgment, and would have to be resolved at trial.” Ibid.
  The District Court was right. The evidence, taken in
the light most favorable to Bucklew, creates a genuine
factual issue as to whether Missouri’s lethal injection
protocol would subject him to several minutes of “severe
pain and suffering,” Glossip, 576 U. S., at ___ (slip op., at
13), during which he would choke and suffocate on his own
blood. In my view, executing Bucklew by forcing him to
choke on his grossly enlarged uvula and suffocate on his
blood would exceed “the limits of civilized standards.”
Kennedy v. Louisiana, 554 U. S. 407, 435 (2008) (internal
quotation marks omitted); see also Trop v. Dulles, 356
U. S. 86, 100–101 (1958) (plurality opinion). The experts
dispute whether Bucklew’s execution will prove as unusu-
ally painful as he claims, but resolution of that dispute is a
matter for trial.
6                  BUCKLEW v. PRECYTHE

                      BREYER, J., dissenting

                               B
   The majority, while characterizing the matter as “criti-
cal,” says that there is “nothing in the record to suggest
that Mr. Bucklew will be capable of experiencing pain for
significantly more than 20 to 30 seconds after being in-
jected with pentobarbital.” Ante, at 26. But what about
Dr. Zivot’s testimony that the time between injection and
death “could range over a few minutes to many minutes”?
App. 222. What about Dr. Zivot’s characterization of the
pain involved as “prolonged”? Id., at 234. What about Dr.
Zivot’s “stron[g] disagree[ment] with [the State’s expert’s]
repeated claim that the pentobarbital injection would
result in ‘rapid unconsciousness’ ”? Id., at 233.
   The majority construes Dr. Zivot’s testimony to show
only that Bucklew might remain alive for several minutes
after the injection, not that he will be capable of feeling
pain for several minutes after the injection. Ante, at 27.
But immediately following his prediction that the time
between injection and death could range up to many
minutes, Dr. Zivot stated that “beginning with the injec-
tion of the Pentobarbital solution and ending with Mr.
Bucklew’s death several minutes to as long as many
minutes later, Mr. Bucklew would be highly likely to
experience feelings of ‘air hunger’ and the excruciating
pain of prolonged suffocation.” App. 222 (emphasis added).
Dr. Zivot thus testified both that lethal injection
would take up to several minutes to kill Bucklew and that
Bucklew would experience excruciating pain during this
period. And it is not the case, as the majority believes,
that Dr. Zivot “carefully avoided claiming that Mr. Buck-
lew would be capable of feeling pain until he died,” ante, at
28, particularly given that the record must be construed in
the light most favorable to Bucklew.
   The majority also justifies its refusal to credit Dr. Zivot’s
testimony on the ground that Dr. Zivot gave a response
during his deposition suggesting that he misinterpreted a
                  Cite as: 587 U. S. ____ (2019)            7

                     BREYER, J., dissenting

study of euthanasia in horses. Ante, at 26–27. Bucklew’s
expert, however, did not rely exclusively or even heavily
upon that study; he mentioned it only in response to a
question posed in his deposition. To the contrary, Dr.
Zivot explained that his testimony regarding the pain to
which Bucklew would be subjected was “supported both by
[his] own professional knowledge of how chemicals of this
type are likely to exert their effects in the body as well as
by the terms of Missouri’s Execution Procedure.” App.
222.
   Whether any mistake about the importance of a single
study makes all the difference to Bucklew’s case is a mat-
ter not for this Court to decide at summary judgment, but
for the factfinder to resolve at trial. As Judge Colloton
pointed out in dissent below, attacks on the “reliability
and credibility of Dr. Zivot’s opinion,” including “his possi-
ble misreading of the horse study on which he partially
relied,” give rise to factual disputes. See 883 F. 3d 1087,
1099 (CA8 2018). Judge Colloton therefore concluded that
“[t]he district court did not err in concluding that it could
not resolve the dispute between the experts on summary
judgment.” Ibid. I agree.
                             II
  This case next presents a legal question. The Court in
Glossip held in the context of a facial challenge to a State’s
execution protocol that the plaintiffs were required not
only to establish that the execution method gave rise to a
“demonstrated risk of severe pain,” but also to identify a
“known and available” alternative method. 576 U. S., at
___ (slip op., at 13). The Court added that the alternative
must be “feasible, readily implemented, and in fact signifi-
cantly reduc[e] a substantial risk of severe pain.” Id., at
___–___ (slip op., at 12–13) (internal quotation marks
omitted).
  I joined the dissent in Glossip, but for present purposes
8                  BUCKLEW v. PRECYTHE

                     BREYER, J., dissenting

I accept the Glossip majority opinion as governing. I
nonetheless do not believe its “alternative method” re-
quirement applies in this case. We “often read general
language in judicial opinion[s] as referring in context to
circumstances similar to the circumstances then before the
Court and not referring to quite different circumstances
that the Court was not then considering.” Illinois v. Lid-
ster, 540 U. S. 419, 424 (2004). And while I acknowledge
that the Court in Glossip spoke in unqualified terms, the
circumstances in Glossip were indeed “different” in rele-
vant respects from the circumstances presented here.
                              A
   The plaintiffs in Glossip undertook an across-the-board
attack against the use of a particular execution method,
which they maintained violated the Eighth Amendment
categorically. In this case, by contrast, Bucklew does not
attack Missouri’s lethal injection protocol categorically, or
even in respect to any execution other than his own.
Instead, he maintains that he is special; that he suffers
from a nearly unique illness; and that, by virtue of that
illness, Missouri’s execution method will be excruciatingly
painful for him even though it would not affect others in
the same way. These differences make a difference.
   First, these differences show that the reasons that un-
derlie Glossip’s “alternative method” requirement do not
apply here.
   The Glossip Court stressed the importance of preventing
method-of-execution challenges from becoming a backdoor
means to abolish capital punishment in general. The
Court wrote that “because it is settled that capital pun-
ishment is constitutional, it necessarily follows that there
must be a constitutional means of carrying it out.” Glos-
sip, 576 U. S., at ___ (slip op., at 4) (alterations omitted).
The Court added that “we have time and again reaffirmed
that capital punishment is not per se unconstitutional.”
                 Cite as: 587 U. S. ____ (2019)           9

                    BREYER, J., dissenting

Id., at ___ (slip op., at 16). And the Court feared that
allowing prisoners to invalidate a State’s method of execu-
tion without identifying an alternative would “effectively
overrule these decisions.” Ibid. But there is no such risk
here. Holding Missouri’s lethal injection protocol uncon-
stitutional as applied to Bucklew—who has a condition
that has been identified in only five people, see supra, at
2–3—would not risk invalidating the death penalty in
Missouri. And, because the State would remain free to
execute prisoners by other permissible means, declining to
extend Glossip’s “alternative method” requirement in this
context would be unlikely to exempt Bucklew or any other
prisoner from the death penalty. Even in the unlikely
event that the State could not identify a permissible alter-
native in a particular case, it would be perverse to treat
that as a reason to execute a prisoner by the method he
has shown to involve excessive suffering.
   The Glossip Court, in adopting the “alternative method”
requirement, relied on THE CHIEF JUSTICE’s plurality
opinion in Baze, which discussed the need to avoid “in-
trud[ing] on the role of state legislatures in implementing
their execution procedures.” 553 U. S., at 51; see also
ante, at 13 (we owe “a measure of deference to a State’s
choice of execution procedures” (internal quotation marks
omitted)). But no such intrusion problem exists in a case
like this one. When adopting a method of execution, a
state legislature will rarely consider the method’s applica-
tion to an individual who, like Bucklew, suffers from a
rare disease. It is impossible to believe that Missouri’s
legislature, when adopting lethal injection, considered the
possibility that it would cause prisoners to choke on their
own blood for up to several minutes before they die. Ex-
empting a prisoner from the State’s chosen method of
execution in these circumstances does not interfere with
any legislative judgment.
   The Court in Glossip may have also believed that the
10                 BUCKLEW v. PRECYTHE

                     BREYER, J., dissenting

identification of a permissible alternative method of execu-
tion would provide a reference point to assist in determin-
ing how much pain in an execution is too much pain. See
576 U. S., at ___–___ (slip op., at 12–13); Baze, 553 U. S.,
at 47, 51 (plurality opinion); see also ante, at 15 (arguing
that determining the constitutionality of a method of
execution “is a necessarily comparative exercise”). But
there is no need for any such reference point in a case like
this. Bucklew accepts the constitutionality of Missouri’s
chosen execution method as to prisoners who do not share
his medical condition. See Brief for Petitioner 36. We are
informed that this method has been used in 20 executions,
apparently without subjecting prisoners to undue pain.
See Brief for Respondents 5. To the extent that any com-
parator is needed, those executions provide a readymade,
built-in comparator against which a court can measure the
degree of excessive pain Bucklew will suffer.
   Second, precedent counsels against extending Glossip.
Neither this Court’s oldest method-of-execution case,
Wilkerson v. Utah, 99 U. S. 130 (1879), nor any subse-
quent decision of this Court until Glossip, held that pris-
oners who challenge a State’s method of execution must
identify an alternative means by which the State may
execute them. To the contrary, in Hill v. McDonough, 547
U. S. 573 (2006), the Court squarely and unanimously
rejected the argument that a prisoner must “identif[y] an
alternative, authorized method of execution.” Id., at 582.
The Court noted that any such requirement would “change
the traditional pleading requirements for §1983 actions,”
which we were not at liberty to do. Ibid. It is thus diffi-
cult to see how the “alternative-method” requirement
could be “compelled by our understanding of the Constitu-
tion,” ante, at 17, even though the Constitution itself never
hints at such a requirement, even though we did not apply
such a requirement in more than a century of method-of-
execution cases, and even though we unanimously rejected
                  Cite as: 587 U. S. ____ (2019)           11

                     BREYER, J., dissenting

such a requirement in Hill. And while the Court in Glos-
sip did not understand itself to be bound by Hill, see Glos-
sip, 576 U. S., at ___ (slip op., at 15) (distinguishing Hill
on the theory that Hill merely rejected a heightened
pleading requirement for §1983 suits), the two decisions
remain in considerable tension. Confining Glossip’s “al-
ternative method” requirement to facial challenges would
help to reconcile them.
   Third, the troubling implications of today’s ruling pro-
vide the best reason for declining to extend Glossip’s “al-
ternative method” requirement. The majority acknowl-
edges that the Eighth Amendment prohibits States from
executing prisoners by “ ‘horrid modes of torture’ ” such as
burning at the stake. Ante, at 10. But the majority’s
decision permits a State to execute a prisoner who suffers
from a medical condition that would render his execution
no less painful. Bucklew has provided evidence of a seri-
ous risk that his execution will be excruciating and gro-
tesque. The majority holds that the State may execute
him anyway. That decision confirms the warning leveled
by the Glossip dissent—that the Court has converted the
Eighth Amendment’s “categorical prohibition into a condi-
tional one.” 576 U. S., at ___ (opinion of SOTOMAYOR, J.)
(slip op., at 24).
                              B
  Even assuming for argument’s sake that Bucklew must
bear the burden of showing the existence of a “known and
available” alternative method of execution that “signifi-
cantly reduces a substantial risk of severe pain,” id., at ___
(majority opinion) (slip op., at 13) (alteration and internal
quotation marks omitted), Bucklew has satisfied that
burden. The record contains more than enough evidence
on the point to raise genuine and material factual issues
that preclude summary judgment.
  Bucklew identified as an alternative method of execu-
12                BUCKLEW v. PRECYTHE

                    BREYER, J., dissenting

tion the use of nitrogen hypoxia, which is a form of execu-
tion by lethal gas. Missouri law permits the use of this
method of execution. See Mo. Rev. Stat. §546.720 (2002).
Three other States—Alabama, Mississippi, and Okla-
homa—have specifically authorized nitrogen hypoxia as a
method of execution. See ante, at 22, n. 1. And Bucklew
introduced into the record reports from Oklahoma and
Louisiana indicating that nitrogen hypoxia would be
simple and painless. These reports summarized the scien-
tific literature as indicating that there is “no reported
physical discom[fort] associated with inhaling pure nitro-
gen,” App. 742, that the “onset of hypoxia is typically so
subtle that it is unnoticeable to the subject,” id., at 745,
and that nitrogen hypoxia would take an estimated
“seventeen-to-twenty seconds” to render a subject uncon-
scious, id., at 746–747. The Oklahoma study concluded that
nitrogen hypoxia is “the most humane method” of execu-
tion available. Id., at 736. And the Louisiana study stat-
ed that the “[u]se of nitrogen as a method of execution can
assure a quick and painless death of the offender.” Id.,
at 746.
   How then can the majority conclude that Bucklew has
failed to identify an alternative method of execution? The
majority finds Bucklew’s evidence inadequate in part
because, in the majority’s view, it does not show that
nitrogen hypoxia will “significantly reduce” Bucklew’s risk
of pain as compared with lethal injection. Ante, at 23. But
the majority does not dispute the evidence suggesting that
nitrogen hypoxia would be “quick and painless” and would
take effect in 20 to 30 seconds. The majority instead
believes that “nothing in the record” suggests that lethal
injection would take longer than nitrogen gas to take
effect. Ante, at 26. As I have already explained, the ma-
jority reaches this conclusion by overlooking considerable
evidence to the contrary—such as Dr. Zivot’s testimony
that Bucklew’s pain would likely prove “prolonged,” App.
                 Cite as: 587 U. S. ____ (2019)           13

                     BREYER, J., dissenting

234, that lethal injection would not “result in ‘rapid un-
consciousness,’ ” id., at 233, and that from the time of
injection to “Mr. Bucklew’s death several minutes to as
long as many minutes later, Mr. Bucklew would be highly
likely to experience . . . the excruciating pain of prolonged
suffocation,” id., at 222. In discounting this evidence, the
majority simply fails “to adhere to the axiom that in ruling
on a motion for summary judgment, the evidence of the
nonmovant is to be believed, and all justifiable inferences
are to be drawn in his favor.” Tolan, 572 U. S., at 651
(internal quotation marks and alteration omitted).
   The majority additionally believes that Bucklew’s evi-
dence fails to show that nitrogen hypoxia would be easy to
implement. Ante, at 21. But the reports from Oklahoma
and Louisiana tell a different story. The Louisiana report
states that nitrogen hypoxia would be “simple to adminis-
ter.” App. 737. The Oklahoma report similarly concludes
that “[d]eath sentences carried out by nitrogen inhalation
would be simple to administer.” Id., at 746; see also id., at
696. The reports explain that nitrogen hypoxia would “not
require the use of a complex medical procedure or phar-
maceutical products,” id., at 747, would “not require the
assistance of licensed medical professionals,” id., 736, and
would require only materials that are “readily available
for purchase,” id., at 739. Further, “[b]ecause the protocol
involved in nitrogen induced hypoxia is so simple, mis-
takes are unlikely to occur.” Id., at 748. And both studies
recommend the development of protocols for actual im-
plementation. See id., at 697 (Oklahoma report recom-
mending development of “a nitrogen hypoxia protocol”);
id., at 736 (Louisiana report noting that although “the
exact protocol” has not been finalized, the report recom-
mends “that hypoxia induced by the inhalation of nitrogen
be considered for adoption”); see also Murphy, Oklahoma
Says It Plans To Use Nitrogen for Executions, USA Today,
Mar. 15, 2018 (quoting the Oklahoma attorney general’s
14                BUCKLEW v. PRECYTHE

                    BREYER, J., dissenting

statement that nitrogen “will be effective, simple to ad-
minister, easy to obtain and requires no complex medical
procedures”); but cf. ante, at 21.
   Presented with evidence such as Bucklew’s, I believe a
State should take at least minimal steps to determine the
feasibility of the proposed alternative. The responsible
state official in this case, however, acknowledged that he
“did not conduct research concerning the feasibility of
lethal gas as a method of execution in Missouri.” Id., at
713; see also Record in No. 14–800 (WD Mo.), Doc. 182–6,
p. 16 (different official acknowledging that, “to be candid,
no, I did not go out and try to find answers to those
questions”).
   The majority sensibly recognizes that an inmate seeking
to identify an alternative method of execution “is not
limited to choosing among those presently authorized by a
particular State’s law.” Ante, at 19. But the majority
faults Bucklew for failing to provide guidance about the
administration of nitrogen hypoxia down to the last detail.
The majority believes that Bucklew failed to present evi-
dence “on essential questions” such as whether the nitro-
gen should be administered “using a gas chamber, a tent,
a hood, [or] a mask”; or “in what concentration (pure ni-
trogen or some mixture of gases)” it should be adminis-
tered; or even how the State might “protec[t the execution
team] against the risk of gas leaks.” Ante, at 21.
   Perhaps Bucklew did not provide these details. But
Glossip did not refer to any of these requirements; today’s
majority invents them. And to insist upon them is to
create what, in a case like this one, would amount to an
insurmountable hurdle for prisoners like Bucklew. That
hurdle, I fear, could permit States to execute even those
who will endure the most serious pain and suffering,
irrespective of how exceptional their case and irrespective
of how thoroughly they prove it. I cannot reconcile the
majority’s decision with a constitutional Amendment that
                  Cite as: 587 U. S. ____ (2019)           15

                     BREYER, J., dissenting

forbids all “cruel and unusual punishments.” Amdt. 8.
                               C
  JUSTICE THOMAS concurs in the majority’s imposition of
an “alternative method” requirement, but would also
permit Bucklew’s execution on the theory that a method of
execution violates the Eighth Amendment “ ‘only if it is
deliberately designed to inflict pain.’ ” Ante, at 1 (concur-
ring opinion) (quoting Baze, 553 U. S., at 94 (THOMAS, J.,
concurring in judgment)). But that is not the proper
standard.
  For one thing, JUSTICE THOMAS’ view would make the
constitutionality of a particular execution turn on the
intent of the person inflicting it. But it is not correct that
concededly torturous methods of execution such as burn-
ing alive are impermissible when imposed to inflict pain
but not when imposed for a subjectively different purpose.
To the prisoner who faces the prospect of a torturous
execution, the intent of the person inflicting the punish-
ment makes no difference.
  For another thing, we have repeatedly held that the
Eighth Amendment is not a static prohibition that pro-
scribes the same things that it proscribed in the 18th
century. Rather, it forbids punishments that would be
considered cruel and unusual today. The Amendment
prohibits “unnecessary suffering” in the infliction of pun-
ishment, which this Court has understood to prohibit
punishments that are “grossly disproportionate to the
severity of the crime” as well as punishments that do not
serve any “penological purpose.” Estelle v. Gamble, 429
U. S. 97, 103, and n. 7 (1976). The Constitution prohibits
gruesome punishments even though they may have been
common at the time of the founding. Few would dispute,
for example, the unconstitutionality of “a new law provid-
ing public lashing, or branding of the right hand, as pun-
ishment . . . [e]ven if it could be demonstrated unequivo-
16                 BUCKLEW v. PRECYTHE

                     BREYER, J., dissenting

cally that these were not cruel and unusual measures in
1791.” Scalia, Originalism: The Lesser Evil, 57 U. Cin. L.
Rev. 849, 861 (1989). The question is not, as JUSTICE
THOMAS maintains, whether a punishment is deliberately
inflicted to cause unnecessary pain, but rather whether we
would today consider the punishment to cause excessive
suffering.
                             III
  Implicitly at the beginning of its opinion and explicitly
at the end, the majority invokes the long delays that now
typically occur between the time an offender is sentenced
to death and his execution. Bucklew was arrested for the
crime that led to his death sentence more than 20 years
ago. And Bucklew’s case is not an anomaly. The average
time between sentencing and execution approaches 18
years and in some instances rises to more than 40 years.
See Glossip, 576 U. S., at ___ (BREYER, J., dissenting) (slip
op., at 18); Reynolds v. Florida, 586 U. S. ___, ___ (2018)
(BREYER, J., statement respecting denial of certiorari) (slip
op., at 2).
  I agree with the majority that these delays are exces-
sive. Undue delays in death penalty cases frustrate the
interests of the State and of surviving victims, who have
“an important interest” in seeing justice done quickly.
Hill, 547 U. S., at 584. Delays also exacerbate the suffer-
ing that accompanies an execution itself. Glossip, 576
U. S., at ___–___ (BREYER, J., dissenting) (slip op., at 19–
23). Delays can “aggravate the cruelty of capital punish-
ment” by subjecting the offender to years in solitary
confinement, and delays also “undermine [capital
punishment’s] jurisprudential rationale” by reducing its
deterrent effect and retributive value. Id., at ___, ___ (slip
op., at 28, 32).
  The majority responds to these delays by curtailing the
constitutional guarantees afforded to prisoners like Buck-
                 Cite as: 587 U. S. ____ (2019)           17

                     BREYER, J., dissenting

lew who have been sentenced to death. By adopting elabo-
rate new rules regarding the need to show an alternative
method of execution, the majority places unwarranted
obstacles in the path of prisoners who assert that an exe-
cution would subject them to cruel and unusual punish-
ment. These obstacles in turn give rise to an unacceptable
risk that Bucklew, or others in yet more difficult circum-
stances, may be executed in violation of the Eighth
Amendment. Given the rarity with which cases like this
one will arise, an unfortunate irony of today’s decision is
that the majority’s new rules are not even likely to im-
prove the problems of delay at which they are directed.
   In support of the need to end delays in capital cases, the
majority refers to Dunn v. Ray, 586 U. S. ___ (2019). In
that case, the Court vacated a stay of execution on the
ground that the prisoner brought his claim too late. The
prisoner in that case, however, brought his claim only five
days after he was notified of the policy he sought to chal-
lenge. See id., at ___ (KAGAN, J., dissenting) (slip op., at
3). And in the view of some of us, the prisoner’s claim—
that prisoners of some faiths were entitled to have a min-
ister present at their executions while prisoners of other
faiths were not—raised a serious constitutional question.
See id., at ___ (slip op., at 2) (characterizing the Court’s
decision as “profoundly wrong”). And therein lies the
problem. It might be possible to end delays by limiting
constitutional protections for prisoners on death row. But
to do so would require us to pay too high a constitutional
price.
   Today’s majority appears to believe that because “[t]he
Constitution allows capital punishment,” ante, at 8, the
Constitution must allow capital punishment to occur
quickly. In reaching that conclusion the majority echoes
an argument expressed by the Court in Glossip, namely,
that “because it is settled that capital punishment is
constitutional, it necessarily follows that there must be a
18                    BUCKLEW v. PRECYTHE

                        BREYER, J., dissenting

constitutional means of carrying it out.” 576 U. S., at ___
(slip op., at 4) (emphasis added; alterations and internal
quotation marks omitted).
   These conclusions do not follow. It may be that there is
no way to execute a prisoner quickly while affording him
the protections that our Constitution guarantees to those
who have been singled out for our law’s most severe sanc-
tion. And it may be that, as our Nation comes to place
ever greater importance upon ensuring that we accurately
identify, through procedurally fair methods, those who
may lawfully be put to death, there simply is no constitu-
tional way to implement the death penalty.
   I have elsewhere written about these problems. See id.,
at ___–___ (BREYER, J., dissenting) (slip op., at 29–33).
And I simply conclude here that the law entitles Bucklew
to an opportunity to prove his claim at trial. I note, how-
ever, that this case adds to the mounting evidence that we
can either have a death penalty that avoids excessive
delays and “arguably serves legitimate penological pur-
poses,” or we can have a death penalty that “seeks reliabil-
ity and fairness in the death penalty’s application” and
avoids the infliction of cruel and unusual punishments.
Id., at ___ (slip op., at 32). It may well be that we “cannot
have both.” Ibid.
                            *     *     *
     I respectfully dissent.
                 Cite as: 587 U. S. ____ (2019)            1

                   SOTOMAYOR, J., dissenting

SUPREME COURT OF THE UNITED STATES
                         _________________

                         No. 17–8151
                         _________________


    RUSSELL BUCKLEW, PETITIONER v. ANNE L.
  PRECYTHE, DIRECTOR, MISSOURI DEPARTMENT
            OF CORRECTIONS, ET AL.
 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
           APPEALS FOR THE EIGHTH CIRCUIT
                        [April 1, 2019]

  JUSTICE SOTOMAYOR, dissenting.
  As I have maintained ever since the Court started down
this wayward path in Glossip v. Gross, 576 U. S. ___
(2015), there is no sound basis in the Constitution for
requiring condemned inmates to identify an available
means for their own executions. JUSTICE BREYER ably
explains why today’s extension of Glossip’s alternative-
method requirement is misguided (even on that prece-
dent’s own terms), and why (with or without that re-
quirement) a trial is needed to determine whether
Missouri’s planned means of executing Russell Bucklew
creates an intolerable risk of suffering in light of his rare
medical condition. I join JUSTICE BREYER’s dissent, except
for Part III. I write separately to address the troubling
dicta with which the Court concludes its opinion.
                              I
  Given the majority’s ominous words about late-arising
death penalty litigation, ante, at 29–30, one might assume
there is some legal question before us concerning delay.
Make no mistake: There is not. The majority’s commen-
tary on once and future stay applications is not only ines-
sential but also wholly irrelevant to its resolution of any
issue before us.
2                  BUCKLEW v. PRECYTHE

                   SOTOMAYOR, J., dissenting

  The majority seems to imply that this litigation has
been no more than manipulation of the judicial process for
the purpose of delaying Bucklew’s execution. Ante, at 29.
When Bucklew commenced this case, however, there was
nothing “settled,” ibid., about whether the interaction of
Missouri’s lethal-injection protocol and his rare medical
condition would be tolerable under the Eighth Amend-
ment. At that time, Glossip had not yet been decided,
much less extended to any as-applied challenge like Buck-
lew’s. In granting prior stay requests in this case, we
acted as necessary to ensure sufficient time for sober
review of Bucklew’s claims. The majority laments those
decisions, but there is nothing unusual—and certainly
nothing untoward—about parties pressing, and courts
giving full consideration to, potentially meritorious consti-
tutional claims, even when those claims do not ultimately
succeed.
                             II
  I am especially troubled by the majority’s statement
that “[l]ast-minute stays should be the extreme exception,”
which could be read to intimate that late-occurring stay
requests from capital prisoners should be reviewed with
an especially jaundiced eye. See ante, at 30. Were those
comments to be mistaken for a new governing standard,
they would effect a radical reinvention of established law
and the judicial role.
  Courts’ equitable discretion in handling stay requests is
governed by well-established principles. See Nken v.
Holder, 556 U. S. 418, 434 (2009). Courts examine the
stay applicant’s likelihood of success on the merits,
whether the applicant will suffer irreparable injury without
a stay, whether other parties will suffer substantial injury
from a stay, and public interest considerations. Ibid.
  It is equally well established that “[d]eath is a punish-
ment different from all other sanctions in kind rather than
                     Cite as: 587 U. S. ____ (2019)                    3

                       SOTOMAYOR, J., dissenting

degree.” Woodson v. North Carolina, 428 U. S. 280, 303–
304 (1976). For that reason, the equities in a death penalty
case will almost always favor the prisoner so long as he
or she can show a reasonable probability of success on the
merits. See Nken, 556 U. S., at 434 (noting that success
on the merits and irreparable injury “are the most critical”
factors); cf. Glossip, 576 U. S., at ___ (slip op., at 11) (ob-
serving, in a preliminary-injunction posture, that “[t]he
parties agree that this case turns on whether petitioners
are able to establish a likelihood of success on the merits”
and analyzing the case accordingly); accord, id., at ___
(SOTOMAYOR, J., dissenting) (slip op., at 22). This accords
with each court’s “ ‘duty to search for constitutional error
with painstaking care’ ” in capital cases. Kyles v. Whitley,
514 U. S. 419, 422 (1995).
    It is of course true that a court may deny relief when a
party has “unnecessarily” delayed seeking it, Nelson v.
Campbell, 541 U. S. 637, 649–650 (2004), and that courts
should not grant equitable relief on clearly “ ‘dilatory,’ ”
“ ‘speculative,’ ” or meritless grounds, ante, at 31 (quoting
Hill v. McDonough, 547 U. S. 573, 584–585 (2006)); see
also Gomez v. United States Dist. Court for Northern Dist.
of Cal., 503 U. S. 653, 654 (1992) (per curiam) (vacating a
stay where an inmate’s unjustified 10-year delay in bring-
ing a claim was an “obvious attempt at manipulation”).
That is hardly the same thing as treating late-arising
claims as presumptively suspect.1
——————
  1 A skewed view of the facts caused the majority to misapply these

principles and misuse its “equitable powers,” see ante, at 30, and n. 5,
in vacating the Court of Appeals’ unanimous stay in Dunn v. Ray, 586
U. S. ___ (2019). Even today’s belated explanation from the majority
rests on the mistaken premise that Domineque Ray could have figured
out sooner that Alabama planned to deny his imam access to the
execution chamber. But see id., at ___ (KAGAN, J., dissenting) (slip op.,
at 3) (noting that the governing statute authorized both the inmate’s
imam and the prison’s Christian chaplain to attend the execution, and
that “the prison refused to give Ray a copy of its own practices and
4                      BUCKLEW v. PRECYTHE

                       SOTOMAYOR, J., dissenting

   The principles of federalism and finality that the major-
ity invokes are already amply served by other constraints
on our review of state judgments—most notably the Anti-
terrorism and Effective Death Penalty Act of 1996, but
also statutes of limitations and other standard filters for
dilatory claims. We should not impose further constraints
on judicial discretion in this area based on little more than
our own policy impulses. Finality and federalism need no
extra thumb on the scale from this Court, least of all with
a human life at stake.
   The only sound approach is for courts to continue to
afford each request for equitable relief a careful hearing
on its own merits. That responsibility is never graver
than when the litigation concerns an impending execution.
See, e.g., Kyles, 514 U. S., at 422; Woodson, 428 U. S., at
303–304. Meritorious claims can and do come to light
even at the eleventh hour, and the cost of cursory review
in such cases would be unacceptably high. See Glossip,
576 U. S., at ___–___ (BREYER, J., dissenting) (slip op., at
21–22) (collecting examples of inmates who came “within
hours or days of execution before later being exonerated”).
A delay, moreover, may be entirely beyond a prisoner’s
control. Execution methods, for example, have been mov-
ing targets subject to considerable secrecy in recent years,
which means that constitutional concerns may surface
only once a State settles on a procedure and communicates
its choice to the prisoner.2 In other contexts, too, fortuity
——————
procedures” that would have clarified the two clergymen’s degrees of
access); Ray v. Commissioner, Ala. Dept. of Corrections, 915 F. 3d 689,
701–703 (CA11 2019).
   2 See Zagorski v. Parker, 586 U. S. ___, ___–___ (2018) (SOTOMAYOR,

J., dissenting from denial of application for stay and denial of certio-
rari) (slip op., at 2–3) (describing Tennessee’s recent equivocation about
the availability of its preferred lethal injection protocol); Glossip, 576
U. S., at ___ (SOTOMAYOR, J., dissenting) (slip op., at 29) (noting States’
“scramble” to formulate “new and untested” execution methods);
Sepulvado v. Jindal, 739 F. 3d 716, 717–718 (CA5 2013) (Dennis, J.,
                      Cite as: 587 U. S. ____ (2019)                     5

                       SOTOMAYOR, J., dissenting

or the imminence of an execution may shake loose consti-
tutionally significant information when time is short.3
  There are higher values than ensuring that executions
run on time. If a death sentence or the manner in which it
is carried out violates the Constitution, that stain can
never come out. Our jurisprudence must remain one of
vigilance and care, not one of dismissiveness.




——————
dissenting from denial of rehearing en banc) (describing Louisiana’s
refusal to inform a prisoner of the drugs that would be used to execute
him); Denno, Lethal Injection Chaos Post-Baze, 102 Geo. L. J. 1331,
1376–1380 (2014) (describing increased secrecy around execution
procedures).
  3 See Connick v. Thompson, 563 U. S. 51, 55–56, and n. 1 (2011) (in-

tentionally suppressed exculpatory crime lab report discovered a month
before a scheduled execution); Ex parte Braziel, No. WR–72,186–01
(Tex. Crim. App., Dec. 11, 2018), pp. 1–2 (Alcala, J., dissenting) (disclo-
sure by the State of “new information about possible prosecutorial
misconduct” the same day as an execution).
