On Wednesday, the United States Supreme Court will review Oklahoma’s three-drug execution protocol. The primary question posed by Glossip v. Gross is whether the use of midazolam as the first drug violates the Eighth Amendment, which prohibits cruel and unusual punishment, by creating a substantial risk of serious harm to condemned prisoners. The Court’s past decisions make clear that an execution procedure violates the Constitution if it presents, to quote the majority opinion in Baze v. Rees, “‘objectively intolerable risk of harm' that prevents prison officials from pleading that they were subjectively blameless for purposes of the Eighth Amendment.”

There should be no doubt in this case: As used in Oklahoma’s execution procedure, midazolam unquestionably creates an “objectively intolerable risk of harm.” Because it is not capable of functioning as a general anesthetic, midazolam provides no relief from searing pain; but, that is exactly what it is expected to do in executions in Oklahoma, Florida, and other states.

Oklahoma executes prisoners by administering midazolam first, followed by a paralytic drug and then potassium chloride. The second drug paralyzes the voluntary muscles, preventing all movement (including facial expressions) and stopping respiration. The third drug, concentrated potassium chloride, stops the heart. In the doses used in executions, potassium chloride has been described as “liquid fire” because without anesthesia it causes intense burning pain upon entering the veins. Midazolam’s role in the execution is to anesthetize the prisoners so that they are unaware of the paralysis caused by the second drug and insensate to the burning pain caused by the third.

Midazolam is a benzodiazepine drug. Its primary clinical use is to provide anxiolysis, amnesia, and sedation. It is not used clinically to induce the type of deep, general anesthesia needed to withstand painful stimuli, and we have good reason to doubt that midazolam, regardless of the size of the dose administered, can reliably produce the “deep comalike unconsciousness” that is necessary to prevent the unconstitutional pain and suffering caused by the potassium chloride in a three-drug lethal injection execution.

Glossip v. Gross will be the second time in seven years that the Court has reviewed a three-drug, lethal injection procedure. In Baze v. Rees (2008), the Court approved Kentucky’s three-drug execution procedure, which was then-used by at least 30 states. In the intervening years, the second and third drugs used in three-drug procedures have remained largely the same.