The main debate in Glossip v. Gross is about the constitutionality of using a protocol of three particular drugs to carry out executions by lethal injection. This debate - contained in the opinion of the Court for five justices by Justice Alito and the dissent for the other four by Justice Sotomayor, is also marked by signs of the justices' distress.
Justice Sotomayor sharply attacks the majority's position that an attack on one method of execution as unconstitutionally cruel cannot succeed unless the attackers show that "any risk of harm was substantial when compared to a known and available method of execution." (Majority opinion at 13.) (Oklahoma, the executing state here, contended that no better drugs were available - because the suppliers of such drugs were not prepared to permit their use in executions.) Justice Sotomayor argued that "under the Court's new rule, it would not matter whether the State intended to use midazolam [the particular drug that posed problems], or instead to have petitioners drawn and quartered, slowly tortured to death, or actually burned at the stake." (Sotomayor, J., dissenting, at 28.)
To this Justice Alito responds that "That is simply not true, and the principal dissent's resort to this outlandish rhetoric reveals the weakness of its legal arguments." (Majority opinion at 29.) He is basically right that Sotomayor's point is wrong. Any of the self-evidently torturous methods of execution she refers to could easily be replaced with other methods that are substantially more humane than these. Doing so might require legislation, but with that step taken these other methods would be "available." Once that's established, it follows that under the majority's test demonstrably torturous methods could not avoid being held unconstitutional.
But Justice Alito's opinion has a striking feature of its own. The inmates' case was that midazolam, which was meant to cause unconsciousness, did not work well enough to maintain unconsciousness when the next two drugs, one for paralyzing the body and thus stopping respiration and the other for stopping the heart, were administered. The second and third drugs, the inmates argued, would cause such excruciating pain that they would jolt people back to consciousness. The result would be, as Justice Sotomayor describes the claim, that the inmates would be "exposed to what may well be the chemical equivalent of being burned at the stake." (Sotomayor, J., dissenting, at 2.) Agonizing things would be done to their bodies, and they would be awake to feel it.
For the Court, Justice Alito responds that the burden of proving this contention lay with the inmates. The lower courts found against the inmates on the facts, and the Supreme Court's role is confined to reviewing those factual rulings for "clear error." Sotomayor makes a good case that in fact there was clear error - perhaps most tellingly, doctors do not use midazolam by itself as an anesthetic for serious surgery, evidently because it cannot be relied upon to so the job of freeing the patient from pain -- but reasonable judges do disagree on this sort of question. (Sotomayor, J., dissenting at 18.)
What's most striking about Alito's opinion, instead, is what he does not say. He never spells out the inmates' claim of chemical torture, or even acknowledges the dissent's identification of this prospect as the crux of the case. Instead he refers repeatedly to the question of whether midazolam will render the inmate "insensate to pain" (the word "insensate" appears in the majority opinion 16 times) or insure unconsciousness despite the "'noxious stimuli'" from the other drugs (the latter language quoted from the trial court). Though he refers many times to the legal standard that requires showing a substantial risk of "severe" pain, he doesn't spell out the inmates' case. Once he refers to arguments concerning "serious" pain (majority opinion at 28), and once he quotes a dissent from another case referring to "a risk of dreadful pain" (id. at 22), but that's as far as he goes.
Why is Alito's language so discrete? Perhaps he felt that the inmates hadn't provided enough evidence to justify even alluding to the idea of chemical torture. Perhaps he regarded the claim as not only unproven but also too preposterous to bear mention. Perhaps he felt that using this language in and of itself gave a rhetorical advantage to the inmates. We do not know, but I think it is fair to take Alito's omission as itself reflecting how troubling he found the case. Where Sotomayor turned to overstatement, Alito chose understatement. Both seem disturbed by what they must address.