(Slip Opinion)
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` OCTOBER TERM, 2014
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`Syllabus
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`1
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` NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
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` being done in connection with this case, at the time the opinion is issued.
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` The syllabus constitutes no part of the opinion of the Court but has been
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` prepared by the Reporter of Decisions for the convenience of the reader.
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` See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.
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`SUPREME COURT OF THE UNITED STATES
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` Syllabus
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` GLOSSIP ET AL. v. GROSS ET AL.
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`
`CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
`
`THE TENTH CIRCUIT
` No. 14–7955. Argued April 29, 2015—Decided June 29, 2015
`
`Because capital punishment is constitutional, there must be a constitu-
`tional means of carrying it out. After Oklahoma adopted lethal injec-
`
`tion as its method of execution, it settled on a three-drug protocol of
`(1) sodium thiopental (a barbiturate) to induce a state of uncon-
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`sciousness, (2) a paralytic agent to inhibit all muscular-skeletal
`movements, and (3) potassium chloride to induce cardiac arrest. In
`Baze v. Rees, 553 U. S. 35, the Court held that this protocol does not
`violate the Eighth Amendment’s prohibition against cruel and unu-
`
`sual punishments. Anti-death-penalty advocates then pressured
`pharmaceutical companies to prevent sodium thiopental (and, later,
`another barbiturate called pentobarbital) from being used in execu-
`tions. Unable to obtain either sodium thiopental or pentobarbital,
`Oklahoma decided to use a 500-milligram dose of midazolam, a seda-
`tive, as the first drug in its three-drug protocol.
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`Oklahoma death-row inmates filed a 42 U. S. C. §1983 action
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`claiming that the use of midazolam violates the Eighth Amendment.
`Four of those inmates filed a motion for a preliminary injunction and
`argued that a 500-milligram dose of midazolam will not render them
`unable to feel pain associated with administration of the second and
`third drugs. After a three-day evidentiary hearing, the District Court
`denied the motion. It held that the prisoners failed to identify a
`known and available alternative method of execution that presented
`a substantially less severe risk of pain. It also held that the prison-
`ers failed to establish a likelihood of showing that the use of midazo-
`lam created a demonstrated risk of severe pain. The Tenth Circuit
`affirmed.
`Held: Petitioners have failed to establish a likelihood of success on the
`merits of their claim that the use of midazolam violates the Eighth
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`GLOSSIP v. GROSS
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`Syllabus
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`Amendment. Pp. 11–29.
`
`(a) To obtain a preliminary injunction, petitioners must establish,
`among other things, a likelihood of success on the merits of their
`claim. See Winter v. Natural Resources Defense Council, Inc., 555
`U. S. 7, 20. To succeed on an Eighth Amendment method-of-
`execution claim, a prisoner must establish that the method creates a
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`demonstrated risk of severe pain and that the risk is substantial
`when compared to the known and available alternatives. Baze, su-
`pra, at 61 (plurality opinion). Pp. 11–13.
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`(b) Petitioners failed to establish that any risk of harm was sub-
`stantial when compared to a known and available alternative method
`of execution. Petitioners have suggested that Oklahoma could exe-
`cute them using sodium thiopental or pentobarbital, but the District
`Court did not commit a clear error when it found that those drugs are
`unavailable to the State. Petitioners argue that the Eighth Amend-
`
`ment does not require them to identify such an alternative, but their
`argument is inconsistent with the controlling opinion in Baze, which
`imposed a requirement that the Court now follows. Petitioners also
`argue that the requirement to identify an alternative is inconsistent
`with the Court’s pre-Baze decision in Hill v. McDonough, 547 U. S.
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`573, but they misread that decision. Hill concerned a question of civ-
`il procedure, not a substantive Eighth Amendment question. That
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`case held that §1983 alone does not require an inmate asserting a
`method-of-execution claim to plead an acceptable alternative. Baze,
`on the other hand, made clear that the Eighth Amendment requires a
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`prisoner to plead and prove a known and available alternative.
`Pp. 13–16.
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`(c) The District Court did not commit clear error when it found that
`midazolam is likely to render a person unable to feel pain associated
`with administration of the paralytic agent and potassium chloride.
`Pp. 16–29.
`(1) Several initial considerations bear emphasis. First, the Dis-
`trict Court’s factual findings are reviewed under the deferential
`“clear error” standard. Second, petitioners have the burden of per-
`suasion on the question whether midazolam is effective. Third, the
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`fact that numerous courts have concluded that midazolam is likely to
`render an inmate insensate to pain during execution heightens the
`deference owed to the District Court’s findings. Finally, challenges to
`lethal injection protocols test the boundaries of the authority and
`competency of federal courts, which should not embroil themselves in
`ongoing scientific controversies beyond their expertise. Baze, supra,
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`at 51. Pp. 16–18.
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`(2) The State’s expert presented persuasive testimony that a 500-
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`milligram dose of midazolam would make it a virtual certainty that
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`Cite as: 576 U. S. ____ (2015)
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`Syllabus
`an inmate will not feel pain associated with the second and third
`drugs, and petitioners’ experts acknowledged that they had no con-
`trary scientific proof. Expert testimony presented by both sides lends
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`support to the District Court’s conclusion. Evidence suggested that a
`500-milligram dose of midazolam will induce a coma, and even one of
`petitioners’ experts agreed that as the dose of midazolam increases, it
`is expected to produce a lack of response to pain. It is not dispositive
`that midazolam is not recommended or approved for use as the sole
`anesthetic during painful surgery. First, the 500-milligram dose at
`issue here is many times higher than a normal therapeutic dose.
`Second, the fact that a low dose of midazolam is not the best drug for
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`maintaining unconsciousness says little about whether a 500-
`milligram dose is constitutionally adequate to conduct an execution.
`Finally, the District Court did not err in concluding that the safe-
`guards adopted by Oklahoma to ensure proper administration of
`midazolam serve to minimize any risk that the drug will not operate
`as intended. Pp. 18–22.
`(3) Petitioners’ speculative evidence regarding midazolam’s “ceil-
`ing effect” does not establish that the District Court’s findings were
`clearly erroneous. The mere fact that midazolam has a ceiling above
`which an increase in dosage produces no effect cannot be dispositive,
`and petitioners provided little probative evidence on the relevant
`question, i.e., whether midazolam’s ceiling effect occurs below the
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`level of a 500-milligram dose and at a point at which the drug does
`not have the effect of rendering a person insensate to pain caused by
`the second and third drugs. Petitioners attempt to deflect attention
`from their failure of proof on this point by criticizing the testimony of
`the State’s expert. They emphasize an apparent conflict between the
`State’s expert and their own expert regarding the biological process
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`that produces midazolam’s ceiling effect. But even if petitioners’ ex-
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`pert is correct regarding that biological process, it is largely beside
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`the point. What matters for present purposes is the dosage at which
`the ceiling effect kicks in, not the biological process that produces the
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`effect. Pp. 22–25.
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`(4) Petitioners’ remaining arguments—that an expert report pre-
`sented in the District Court should have been rejected because it ref-
`erenced unreliable sources and contained an alleged mathematical
`error, that only four States have used midazolam in an execution,
`and that difficulties during two recent executions suggest that mid-
`azolam is ineffective—all lack merit. Pp. 26–29.
`776 F. 3d 721, affirmed.
`ALITO, J., delivered the opinion of the Court, in which ROBERTS, C. J.,
`and SCALIA, KENNEDY, and THOMAS, JJ., joined. SCALIA, J., filed a con-
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`4
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`GLOSSIP v. GROSS
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`Syllabus
`curring opinion, in which THOMAS, J., joined. THOMAS, J., filed a con-
`curring opinion, in which SCALIA, J., joined. BREYER, J., filed a dissent-
`ing opinion, in which GINSBURG, J., joined. SOTOMAYOR, J., filed a dis-
`senting opinion, in which GINSBURG, BREYER, and KAGAN, JJ., joined.
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`Cite as: 576 U. S. ____ (2015)
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`Opinion of the Court
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`1
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` NOTICE: This opinion is subject to formal revision before publication in the
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` preliminary print of the United States Reports. Readers are requested to
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` notify the Reporter of Decisions, Supreme Court of the United States, Wash-
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` ington, D. C. 20543, of any typographical or other formal errors, in order
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` that corrections may be made before the preliminary print goes to press.
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`SUPREME COURT OF THE UNITED STATES
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`_________________
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` No. 14–7955
`_________________
` RICHARD E. GLOSSIP, ET AL., PETITIONERS v.
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`
`
`KEVIN J. GROSS, ET AL.
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`
`ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
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`
`APPEALS FOR THE TENTH CIRCUIT
`
`[June 29, 2015]
`
`JUSTICE ALITO delivered the opinion of the Court.
`Prisoners sentenced to death in the State of Oklahoma
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`filed an action in federal court under Rev. Stat. §1979, 42
`U. S. C. §1983, contending that the method of execution
`now used by the State violates the Eighth Amendment
`because it creates an unacceptable risk of severe pain.
`
`They argue that midazolam, the first drug employed in the
`State’s current three-drug protocol, fails to render a per-
`son insensate to pain. After holding an evidentiary hear-
`ing, the District Court denied four prisoners’ application
`for a preliminary injunction, finding that they had failed
`to prove that midazolam is ineffective. The Court of Ap-
`peals for the Tenth Circuit affirmed and accepted the
`District Court’s finding of fact regarding midazolam’s
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`efficacy.
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`For two independent reasons, we also affirm. First, the
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`prisoners failed to identify a known and available alterna-
`tive method of execution that entails a lesser risk of pain,
`a requirement of all Eighth Amendment method-of-
`execution claims. See Baze v. Rees, 553 U. S. 35, 61 (2008)
`(plurality opinion). Second, the District Court did not
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`2
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`GLOSSIP v. GROSS
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`Opinion of the Court
`commit clear error when it found that the prisoners failed
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`to establish that Oklahoma’s use of a massive dose of
`midazolam in its execution protocol entails a substantial
`risk of severe pain.
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`I
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`
`A
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`The death penalty was an accepted punishment at the
`
`time of the adoption of the Constitution and the Bill of
`Rights. In that era, death sentences were usually carried
`out by hanging. The Death Penalty in America: Current
`Controversies 4 (H. Bedau ed. 1997). Hanging remained
`the standard method of execution through much of the
`19th century, but that began to change in the century’s
`later years. See Baze, supra, at 41–42. In the 1880’s, the
`Legislature of the State of New York appointed a commis-
`sion to find “‘the most humane and practical method
`known to modern science of carrying into effect the sen-
`tence of death in capital cases.’” In re Kemmler, 136 U. S.
`436, 444 (1890). The commission recommended electrocu-
`tion, and in 1888, the Legislature enacted a law providing
`for this method of execution. Id., at 444–445. In subse-
`quent years, other States followed New York’s lead in the
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`“‘belief that electrocution is less painful and more humane
`than hanging.’” Baze, 553 U. S., at 42 (quoting Malloy v.
`South Carolina, 237 U. S. 180, 185 (1915)).
`
`In 1921, the Nevada Legislature adopted another new
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`method of execution, lethal gas, after concluding that this
`was “the most humane manner known to modern science.”
`State v. Jon, 46 Nev. 418, 437, 211 P. 676, 682 (1923). The
`Nevada Supreme Court rejected the argument that the
`use of lethal gas was unconstitutional, id., at 435–437, 211
`P., at 681–682, and other States followed Nevada’s lead,
`see, e.g., Ariz. Const., Art. XXII, §22 (1933); 1937 Cal.
`Stats. ch. 172, §1; 1933 Colo. Sess. Laws ch. 61, §1; 1955
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`Md. Laws ch. 625, §1, p. 1017; 1937 Mo. Laws p. 222, §1.
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`Opinion of the Court
`Nevertheless, hanging and the firing squad were retained
`in some States, see, e.g., 1961 Del. Laws ch. 309, §2 (hang-
`ing); 1935 Kan. Sess. Laws ch. 155, §1 (hanging); Utah
`Code Crim. Proc. §105–37–16 (1933) (hanging or firing
`squad), and electrocution remained the predominant
`method of execution until the 9-year hiatus in executions
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`that ended with our judgment in Gregg v. Georgia, 428
`U. S. 153 (1976). See Baze, supra, at 42.
`After Gregg reaffirmed that the death penalty does not
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`violate the Constitution, some States once again sought a
`more humane way to carry out death sentences. They
`eventually adopted lethal injection, which today is “by far
`the most prevalent method of execution in the United
`States.” Baze, supra, at 42. Oklahoma adopted lethal
`injection in 1977, see 1977 Okla. Sess. Laws p. 89, and it
`eventually settled on a protocol that called for the use of
`three drugs: (1) sodium thiopental, “a fast-acting barbitu-
`rate sedative that induces a deep, comalike unconscious-
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`ness when given in the amounts used for lethal injection,”
`(2) a paralytic agent, which “inhibits all muscular-skeletal
`movements and, by paralyzing the diaphragm, stops respi-
`ration,” and (3) potassium chloride, which “interferes with
`the electrical signals that stimulate the contractions of the
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`heart, inducing cardiac arrest.” Baze, supra, at 44; see
`also Brief for Respondents 9. By 2008, at least 30 of the
`36 States that used lethal injection employed that particu-
`lar three-drug protocol. 553 U. S., at 44.
`
`While methods of execution have changed over the
`years, “[t]his Court has never invalidated a State’s chosen
`procedure for carrying out a sentence of death as the
`infliction of cruel and unusual punishment.” Id., at 48. In
`Wilkerson v. Utah, 99 U. S. 130, 134–135 (1879), the Court
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`upheld a sentence of death by firing squad. In In re
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`Kemmler, supra, at 447–449, the Court rejected a chal-
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`lenge to the use of the electric chair. And the Court did
`not retreat from that holding even when presented with a
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`GLOSSIP v. GROSS
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`Opinion of the Court
`case in which a State’s initial attempt to execute a pris-
`oner by electrocution was unsuccessful. Louisiana ex rel.
`Francis v. Resweber, 329 U. S. 459, 463–464 (1947) (plu-
`rality opinion). Most recently, in Baze, supra, seven Jus-
`tices agreed that the three-drug protocol just discussed
`does not violate the Eighth Amendment.
`
`Our decisions in this area have been animated in part
`by the recognition that because it is settled that capital
`punishment is constitutional, “[i]t necessarily follows that
`there must be a [constitutional] means of carrying it out.”
`Id., at 47. And because some risk of pain is inherent in
`any method of execution, we have held that the Constitu-
`tion does not require the avoidance of all risk of pain.
`
`Ibid. After all, while most humans wish to die a painless
`death, many do not have that good fortune. Holding that
`the Eighth Amendment demands the elimination of essen-
`tially all risk of pain would effectively outlaw the death
`penalty altogether.
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`
`B
`Baze cleared any legal obstacle to use of the most com-
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`mon three-drug protocol that had enabled States to carry
`out the death penalty in a quick and painless fashion. But
`a practical obstacle soon emerged, as anti-death-penalty
`advocates pressured pharmaceutical companies to refuse
`to supply the drugs used to carry out death sentences.
`The sole American manufacturer of sodium thiopental, the
`first drug used in the standard three-drug protocol, was
`persuaded to cease production of the drug. After suspend-
`ing domestic production in 2009, the company planned to
`resume production in Italy. Koppel, Execution Drug Halt
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`Raises Ire of Doctors, Wall Street Journal, Jan. 25, 2011,
`p. A6. Activists then pressured both the company and the
`Italian Government to stop the sale of sodium thiopental
`for use in lethal injections in this country. Bonner, Letter
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`from Europe: Drug Company in Cross Hairs of Death
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`Opinion of the Court
`Penalty Opponents, N. Y. Times, Mar. 30, 2011; Koppel,
`Drug Halt Hinders Executions in the U. S., Wall Street
`Journal, Jan. 22, 2011, p. A1. That effort proved success-
`ful, and in January 2011, the company announced that it
`would exit the sodium thiopental market entirely. See
`Hospira, Press Release, Hospira Statement Regarding
`PentothalTM (sodium thiopental) Market Exit (Jan. 21,
`2011).
`After other efforts to procure sodium thiopental proved
`
`unsuccessful, States sought an alternative, and they even-
`tually replaced sodium thiopental with pentobarbital,
`another barbiturate. In December 2010, Oklahoma be-
`came the first State to execute an inmate using pentobar-
`bital. See Reuters, Chicago Tribune, New Drug Mix Used
`
`in Oklahoma Execution, Dec. 17 2010, p. 41. That execu-
`tion occurred without incident, and States gradually shifted
`to pentobarbital as their supplies of sodium thiopental
`ran out. It is reported that pentobarbital was used in all
`of the 43 executions carried out in 2012. The Death
`Penalty Institute, Execution List 2012, online at www.
`
`Internet
`deathpenaltyinfo.org/execution-list-2012
`(all
`materials as visited June 26, 2015, and available in Clerk
`of Court’s case file). Petitioners concede that pentobarbi-
`tal, like sodium thiopental, can “reliably induce and main-
`tain a comalike state that renders a person insensate to
`pain” caused by administration of the second and third
`drugs in the protocol. Brief for Petitioners 2. And courts
`across the country have held that the use of pentobarbital
`in executions does not violate the Eighth Amendment.
`
`See, e.g., Jackson v. Danberg, 656 F. 3d 157 (CA3 2011);
`Beaty v. Brewer, 649 F. 3d 1071 (CA9 2011); DeYoung v.
`Owens, 646 F. 3d 1319 (CA11 2011); Pavatt v. Jones, 627
`F. 3d 1336 (CA10 2010).
`Before long, however, pentobarbital also became una-
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`vailable. Anti-death-penalty advocates lobbied the Danish
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`manufacturer of the drug to stop selling it for use in exe-
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`GLOSSIP v. GROSS
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`Opinion of the Court
`cutions. See Bonner, supra. That manufacturer opposed
`the death penalty and took steps to block the shipment of
`pentobarbital for use in executions in the United States.
`Stein, New Obstacle to Death Penalty in U. S., Washing-
`ton Post, July 3, 2011, p. A4. Oklahoma eventually be-
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`came unable to acquire the drug through any means. The
`District Court below found that both sodium thiopental
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`and pentobarbital are now unavailable to Oklahoma. App.
`67–68.
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`C
`Unable to acquire either sodium thiopental or pentobar-
`
`bital, some States have turned to midazolam, a sedative in
`the benzodiazepine family of drugs. In October 2013,
`Florida became the first State to substitute midazolam for
`pentobarbital as part of a three-drug lethal injection pro-
`tocol. Fernandez, Executions Stall As States Seek Differ-
`ent Drugs, N. Y. Times, Nov. 9, 2013, p. A1. To date,
`Florida has conducted 11 executions using that protocol,
`which calls for midazolam followed by a paralytic agent
`and potassium chloride. See Brief for State of Florida as
`Amicus Curiae 2–3; Chavez v. Florida SP Warden, 742
`
`F. 3d 1267, 1269 (CA11 2014). In 2014, Oklahoma also
`substituted midazolam for pentobarbital as part of its
`three-drug protocol. Oklahoma has already used this
`three-drug protocol twice: to execute Clayton Lockett in
`April 2014 and Charles Warner in January 2015. (Warner
`was one of the four inmates who moved for a preliminary
`injunction in this case.)
`The Lockett execution caused Oklahoma to implement
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`new safety precautions as part of its lethal injection proto-
`col. When Oklahoma executed Lockett, its protocol called
`for the administration of 100 milligrams of midazolam, as
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`compared to the 500 milligrams that are currently re-
`quired. On the morning of his execution, Lockett cut
`himself twice at “‘the bend of the elbow.’” App. 50. That
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`Opinion of the Court
` evening, the execution team spent nearly an hour making
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`at least one dozen attempts to establish intravenous (IV)
`access to Lockett’s cardiovascular system, including at his
`arms and elsewhere on his body. The team eventually
`believed that it had established intravenous access
`through Lockett’s right femoral vein, and it covered the
`injection access point with a sheet, in part to preserve
`Lockett’s dignity during the execution. After the team
`administered the midazolam and a physician determined
`that Lockett was unconscious, the team next administered
`the paralytic agent (vecuronium bromide) and most of the
`potassium chloride. Lockett began to move and speak, at
`which point the physician lifted the sheet and determined
`that the IV had “infiltrated,” which means that “the IV
`fluid, rather than entering Lockett’s blood stream, had
`leaked into the tissue surrounding the IV access point.”
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`Warner v. Gross, 776 F. 3d 721, 725 (CA10 2015) (case
`below). The execution team stopped administering the
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`remaining potassium chloride and terminated the execu-
`tion about 33 minutes after the midazolam was first in-
`jected. About 10 minutes later, Lockett was pronounced
`dead.
`
`An investigation into the Lockett execution concluded
`that “the viability of the IV access point was the single
`greatest factor that contributed to the difficulty in admin-
`istering the execution drugs.” App. 398. The investiga-
`tion, which took five months to complete, recommended
`several changes to Oklahoma’s execution protocol, and
`Oklahoma adopted a new protocol with an effective date of
`September 30, 2014. That protocol allows the Oklahoma
`Department of Corrections to choose among four different
`drug combinations. The option that Oklahoma plans to
`use to execute petitioners calls for the administration of
`500 milligrams of midazolam followed by a paralytic agent
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`GLOSSIP v. GROSS
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`Opinion of the Court
` and potassium chloride.1 The paralytic agent may be
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` pancuronium bromide, vecuronium bromide, or rocuronium
`bromide, three drugs that, all agree, are functionally
`equivalent for purposes of this case. The protocol also
`includes procedural safeguards to help ensure that an
`inmate remains insensate to any pain caused by the ad-
`ministration of the paralytic agent and potassium chlo-
`ride. Those safeguards include: (1) the insertion of both a
`primary and backup IV catheter, (2) procedures to confirm
`the viability of the IV site, (3) the option to postpone an
`execution if viable IV sites cannot be established within an
`hour, (4) a mandatory pause between administration of
`the first and second drugs, (5) numerous procedures for
`monitoring the offender’s consciousness, including the use
`of an electrocardiograph and direct observation, and
`(6) detailed provisions with respect to the training and
`preparation of the execution team. In January of this
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`year, Oklahoma executed Warner using these revised
`procedures and the combination of midazolam, a paralytic
`agent, and potassium chloride.
`
`II
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`
`
`A
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`In June 2014, after Oklahoma switched from pentobar-
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`bital to midazolam and executed Lockett, 21 Oklahoma
`death row inmates filed an action under 42 U. S. C. §1983
`challenging the State’s new lethal injection protocol. The
`complaint alleged that Oklahoma’s use of midazolam
`violates the Eighth Amendment’s prohibition of cruel and
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`unusual punishment.
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`In November 2014, four of those plaintiffs—Richard
`
`——————
` 1The three other drug combinations that Oklahoma may admin-
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`ister are: (1) a single dose of pentobarbital, (2) a single dose of
`sodium thiopental, and (3) a dose of midazolam followed by a dose of
`hydromorphone.
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`Opinion of the Court
`Glossip, Benjamin Cole, John Grant, and Warner—filed a
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`motion for a preliminary injunction. All four men had
`been convicted of murder and sentenced to death by Okla-
`homa juries. Glossip hired Justin Sneed to kill his em-
`ployer, Barry Van Treese. Sneed entered a room where
`Van Treese was sleeping and beat him to death with a
`baseball bat. See Glossip v. State, 2007 OK CR 12, 157
`P. 3d 143, 147–149. Cole murdered his 9-month-old
`daughter after she would not stop crying. Cole bent her
`body backwards until he snapped her spine in half. After
`the child died, Cole played video games. See Cole v. State,
`2007 OK CR 27, 164 P. 3d 1089, 1092–1093. Grant, while
`serving terms of imprisonment totaling 130 years, killed
`Gay Carter, a prison food service supervisor, by pulling
`her into a mop closet and stabbing her numerous times
`with a shank. See Grant v. State, 2002 OK CR 36, 58
`P. 3d 783, 789. Warner anally raped and murdered an 11-
`month-old girl. The child’s injuries included two skull
`
`fractures, internal brain injuries, two fractures to her jaw,
`a lacerated liver, and a bruised spleen and lungs. See
`Warner v. State, 2006 OK CR 40, 144 P. 3d 838, 856–857.
`
`
`The Oklahoma Court of Criminal Appeals affirmed the
`murder conviction and death sentence of each offender.
`Each of the men then unsuccessfully sought both state
`postconviction and federal habeas corpus relief. Having
`
`exhausted the avenues for challenging their convictions
`and sentences, they moved for a preliminary injunction
`against Oklahoma’s lethal injection protocol.
`B
`
`In December 2014, after discovery, the District Court
`held a 3-day evidentiary hearing on the preliminary in-
`junction motion. The District Court heard testimony from
`17 witnesses and reviewed numerous exhibits. Dr. David
`Lubarsky, an anesthesiologist, and Dr. Larry Sasich, a
`doctor of pharmacy, provided expert testimony about
`
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`9
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`

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`10
`
`
`GLOSSIP v. GROSS
`
`Opinion of the Court
`midazolam for petitioners, and Dr. Roswell Evans, a
`
`for
`doctor of pharmacy, provided expert testimony
`respondents.
`
`
`After reviewing the evidence, the District Court issued
`an oral ruling denying the motion for a preliminary in-
`junction. The District Court first rejected petitioners’
`challenge under Daubert v. Merrell Dow Pharmaceuticals,
`
`Inc., 509 U. S. 579 (1993), to the testimony of Dr. Evans.
`It concluded that Dr. Evans, the Dean of Auburn Universi-
`ty’s School of Pharmacy, was well qualified to testify about
`midazolam’s properties and that he offered reliable testi-
`
`mony. The District Court then held that petitioners failed
`to establish a likelihood of success on the merits of their
`claim that the use of midazolam violates the Eighth
`Amendment. The court provided two independent reasons
`for this conclusion. First, the court held that petitioners
`failed to identify a known and available method of execu-
`tion that presented a substantially less severe risk of pain
`than the method that the State proposed to use. Second,
`the court found that petitioners failed to prove that Okla-
`homa’s protocol “presents a risk that is ‘sure or very likely
`to cause serious illness and needless suffering,’ amounting
`to ‘an objectively intolerable risk of harm.’” App. 96 (quot-
`ing Baze, 553 U. S., at 50). The court emphasized that the
`Oklahoma protocol featured numerous safeguards, includ-
`ing the establishment of two IV access sites, confirmation
`of the viability of those sites, and monitoring of the offend-
`er’s level of consciousness throughout the procedure.
`
`The District Court supported its decision with findings
`of fact about midazolam. It found that a 500-milligram
`dose of midazolam “would make it a virtual certainty that
`any individual will be at a sufficient level of unconscious-
`ness to resist the noxious stimuli which could occur from
`
`the application of the second and third drugs.” App. 77.
`Indeed, it found that a 500-milligram dose alone would
`
`likely cause death by respiratory arrest within 30 minutes
`
`
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`

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`
` Cite as: 576 U. S. ____ (2015)
`
`Opinion of the Court
`
`
`
` 11
`
`
`
`or an hour.
`
`The Court of Appeals for the Tenth Circuit affirmed.
`776 F. 3d 721. The Court of Appeals explained that our
`decision in Baze requires a plaintiff challenging a lethal
`
`injection protocol to demonstrate that the risk of severe
`pain presented by an execution protocol is substantial
`“‘when compared to the known and available alterna-
`tives.’” Id., at 732 (quoting Baze, supra, at 61). And it
`agreed with the District Court that petitioners had not
`identified any such alternative. The Court of Appeals
`added, however, that this holding was “not outcome-
`determinative in this case” because petitioners additionally
`failed to establish that the use of midazolam creates a
`
`demonstrated risk of severe pain. 776 F. 3d, at 732. The
`
`Court of Appeals found that the District Court did not
`abuse its discretion by relying on Dr. Evans’ testimony,
`and it concluded that the District Court’s factual findings
`about midazolam were not clearly erroneous. It also held
`that alleged errors in Dr. Evans’ testimony did not render
`his testimony unreliable or the District Court’s findings
`clearly erroneous.
`
`Oklahoma executed Warner on January 15, 2015, but
`we subsequently voted to grant review and then stayed
`the executions of Glossip, Cole, and Grant pending the
`
`resolution of this case. 574 U. S. ___ (2015).
`
`III
`
`“A plaintiff seeking a preliminary injunction must estab-
`lish that he is likely to succeed on the merits, that he is
`likely to suffer irreparable harm in the absence of prelimi-
`nary relief, that the balance of equities tips in his favor,
`and that an injunction is in the public interest.” Winter v.
`Natural Resources Defense Council, Inc., 555 U. S. 7, 20
`(2008). The parties agree that this case turns on whether
`
`petitioners are able to establish a likelihood of success on
`the merits.
`
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`

`
`12
`
`
`GLOSSIP v. GROSS
`
`Opinion of the Court
`The Eighth Amendment, made applicable to the States
`
`through the Fourteenth Amendment, prohibits the inflic-
`tion of “cruel and unusual punishments.” The controlling
`opinion in Baze outlined what a prisoner must establish to
`succeed on an Eighth Amendment method-of-execution
`claim. Baze involved a challenge by Kentucky death row
`inmates to that State’s three-drug lethal injection protocol
`of sodium thiopental, pancuronium bromide, and potassium
`
`chloride. The inmates conceded that the protocol, if
`properly administered, would result in a humane and
`constitutional execution because sodium thiopental would
`render an inmate oblivious to any pain caused by the
`second and third drugs. 553 U. S., at 49. But they argued
`
`that there was an unacceptable risk that sodium thiopen-
`tal would not be properly administered. Ibid. The in-
`mates also maintained that a significant risk of harm
`could be eliminated if Kentucky adopted a one-drug proto-
`col and additional monitoring by trained personnel. Id., at
`51.
`The controlling opinion in Baze first concluded that
`
`prisoners cannot successfully challenge a method of execu-
`tion unless they establish that the method presents a risk
`that is “‘sure or very likely to cause serious illness and
`
`needless suffering,’ and give rise to ‘sufficiently imminent
`dangers.’” Id., at 50 (quoting Helling v. McKinney, 509
`U. S. 25, 33, 34–35 (1993)). To prevail on such a claim,
`“there must be a ‘substantial risk of serious harm,’ an
`‘objectively intolerable risk of harm’ that prevents prison
`officials from pleading that they were ‘subjectively blame-
`
`less for purposes of the Eighth Amendment.’” 553 U. S.,
`at 50 (quoting Farmer v. Brennan, 511 U. S. 825, 846, and
`n. 9 (1994)). The controlling opinion also stated that
`prisoners “cannot successfully challenge a State’s method
`of execution merely by showing a slightly or marginally
`safer alternative.” 553 U. S., at 51. Instead, prisoners
`
`must identify an alternative that is “feasible, readily
`