An Oklahoma man who reportedly said “I feel my whole body burning” as he was executed by lethal injection Thursday was killed using a controversial mix of drugs that civil rights groups says constitutes cruel and unusual punishment.
Michael Lee Wilson, 38, was executed using a cocktail of drugs including pentobarbital, prison officials confirmed to TIME. The use of pentobarbital in lethal executions has become increasingly common since sodium thiopental, the drug historically used as an anesthetic, became unavailable in 2011 after the manufacturer stopped supplying it for executions.
But pentobarbital is considered a controversial substitute for sodium thiopental because its manufacture is often poorly regulated, and contaminated batches can cause exruciating pain prior to death.
Tanya Greene, advocacy and policy counsel on criminal justice issues for the ACLU, said the use of pentobarbitol in executions is unconstitutional as it violates the Eighth Amendment’s protection against cruel and unusual punishment. Use of the drug in executions, she said, is “basically an experiment on human beings; the risk of extended, painful death is very high. The European manufacturer of pentobarbital objects to its use to kill and has stopped selling the drug to US states for use in executions.”
Wilson’s cry that he felt his “whole body burning” after he was injected with the drug may bolster civil rights groups’ case that pentobarbital should be banned from use in lethal injections.
Lundbeck, a Danish pharmaceutical company that produces pentobarbital, announced in 2011 that it would stop supplying the drug for use in lethal injections since Denmark abolished the death penalty years ago. Lundbeck’s refusal to supply pentobarbital to U.S. prisons has caused a drug shortage that has led some prisons to use a synthetic version of the drug made in compounding pharmacies, which are not regulated by the FDA, according to Mother Jones. These unregulated drugs have been subjected to less rigorous testing, and may include contaminants that cause significant pain.
Oklahoma Department of Corrections spokesman Jerry Massie was unable to comment on the source of the pentobarbital used to kill Wilson.
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Wilson was convicted of robbery and first-degree murder in the killing of one of his convenience store co-workers in 1995. Two of his accomplices were already executed, and a third is serving a life sentence, Fox News reports.
Before he was injected, he said “I love everybody.” Then once the Warden ordered the execution to begin, he said “I love the world. Love my daughters for me. I’m going to miss you always.” Wilson’s mother, sister, and fiancee were present at the execution.
Additional reporting by the Associated Press.