The Supreme Court will consider on Wednesday whether Oklahoma's execution protocol violates the constitutional ban on cruel and unusual punishment, in a case that could have huge implications for how states carry out the death penalty.
The arguments will take place exactly one year after the state botched the execution of Clayton Lockett, in a lethal injection that lasted 43 minutes with the inmate awake well after he was supposed to be unconscious. Another execution in Arizona lasted nearly two hours. A third in Ohio lasted 26 minutes.
Although the doses and drug pairings varied from state to state, each used midazolam in an attempt to sedate the inmate.
In Oklahoma, the state follows midazolam up with a paralytic, and then potassium chloride, which is intended to stop the heart.
"Potassium chloride feels like liquid fire as it courses through the veins," attorneys representing three Oklahoma death row inmates write. "The administration of painful drugs is constitutional only if the prisoner is first placed in a deep, coma-like state of unconsciousness," something that midazolam is incapable of, they argue.
Unlike sodium thiopental, which was previously used by states in a three-drug execution protocol, midazolam has not been approved by the Food and Drug Administration as the sole anesthetic before surgery. Midazolam is instead used to reduce anxiety before anesthesia, or is used for less intense procedures like colonoscopies.
Oklahoma counters that the concerns are "theoretical speculation" — that the state's botch was the result of IV issues unrelated to the drug.
"Oklahoma's robust procedural safeguards will eliminate any risk that Petitioners will experience severe pain during their executions," Attorney General Scott Pruitt wrote.
Medical experts say midazolam has a "ceiling effect," meaning that at a certain dosage, the drug will no longer produce a deeper effect.
But Oklahoma points to Dr. Lee Evans, the dean of the Auburn University Harrison School of Pharmacy, who says the dose Oklahoma uses "make[s] it a virtual certainty that any individual will be at a sufficient level of unconsciousness."
Lower courts agreed.
"Dr. Evans testified persuasively, in substance, that whatever the ceiling effect of midazolam may be with respect to anesthesia... there is no ceiling effect with respect to the ability of a 500 milligram dose of midazolam to effectively paralyze the brain," the district court wrote in a decision.
Sixteen pharmacology experts disagreed in an amicus brief filed on behalf of neither party.
"There is overwhelming scientific consensus, including among pharmacologists, that midazolam is incapable of inducing a 'deep, coma-like unconsciousness,'" they wrote. "Even an excessive dose of midazolam will not result in unconsciousness."
Through an assistant, Evans declined a request to be interviewed by BuzzFeed News.
This is the first execution drug case the Supreme Court case has taken since 2008, when the court upheld a different three-drug protocol. And while the case itself centers on the use of midazolam, the court's ruling could have a ripple effect on how executions are carried out.
If the court decides that midazolam is not capable of sufficiently rendering the inmates unconscious, there will be one fewer option in an already limited pool of potential lethal injection schemes.
"It's hard to say what states would do," said Jen Moreno, a lawyer with Berkeley Law's Death Penalty Clinic. Moreno has informally advised the team representing death row inmates.
"I think the fact that Missouri, Georgia, and Texas are still getting compounded pentobarbital shows that that could still be an option," she said. "If that's not the route that they go, they are looking at different drugs."
There is another option, however, one that several states have considered: to pursue options outside of lethal injection.
Last month, Utah Gov. Gary Herbert signed a law allowing the state to use a firing squad. Oklahoma has approved nitrogen gas as an option if lethal injection is ruled unconstitutional.
"I believe capital punishment must be performed effectively and without cruelty," Oklahoma Gov. Mary Fallin said after signing the bill. "The bill I signed gives the state of Oklahoma another death penalty option that meets that standard."