Page:Glossip v. Gross.pdf/107

 Cite as: 576 U. S. ____ (2015)

11

SOTOMAYOR, J., dissenting

the Court disregards an objectively intolerable risk of severe pain. A Like the Court, I would review for clear error the Dis­ trict Court’s finding that 500 milligrams of midazolam will render someone sufficiently unconscious “ ‘to resist the noxious stimuli which could occur from the application of the second and third drugs.’ ” Ante, at 18–19 (quoting App. 77). Unlike the Court, however, I would do so without abdicating our duty to examine critically the factual predi­ cates for the District Court’s finding—namely, Dr. Evans’ testimony that midazolam has a “ceiling effect” only “at the spinal cord level,” and that a “500 milligram dose of midazolam” can therefore “effectively paralyze the brain.” Id., at 78. To be sure, as the Court observes, such scien­ tific testimony may at times lie at the boundaries of fed­ eral courts’ expertise. See ante, at 17–18. But just because a purported expert says something does not make it so. Especially when important constitutional rights are at stake, federal district courts must carefully evaluate the premises and evidence on which scientific conclusions are based, and appellate courts must ensure that the courts below have in fact carefully considered all the evidence presented. Clear error exists “when although there is evidence to support” a finding, “the reviewing court on the entire evidence is left with the definite and firm conviction that a mistake has been committed.” United States v. United States Gypsum Co., 333 U. S. 364, 395 (1948). Here, given the numerous flaws in Dr. Evans’ testimony, there can be little doubt that the District Court clearly erred in relying on it. To begin, Dr. Evans identified no scientific literature to support his opinion regarding midazolam’s properties at higher-than-normal doses. Apart from a Material Safety Data Sheet that was relevant only insofar as it suggests