Alabama is slated to perform an execution using nitrogen gas Thursday night, in what will be the first time this method has been used in the United States.
The decision comes after the U.S. Supreme Court and a federal appeals court on Wednesday declined to halt the Yellowhammer State’s planned execution of Kenneth Eugene Smith, an inmate in Alabama.
The execution by nitrogen hypoxia involves depriving a person of the oxygen needed to maintain bodily functions. The chemical element makes up 78 percent of the air inhaled by humans and is harmless when inhaled with oxygen.
Smith, 58, is one of two men convicted in the 1988 murder-for-hire killing in which he and an accomplice stabbed Elizabeth Sennett 10 times in Alabama’s Colbert County.
The planned execution has sparked controversy, with some human rights advocates arguing the method could amount to torture, cruel, inhumane or degrading treatment under international human rights law.
The U.N. Human Rights Office earlier this month said it is “alarmed” by the execution and noted Alabama does not have a provision for sedation prior to employing the method, even though large animals are often sedated when executed by nitrogen gas.
The nation’s highest court on Wednesday rejected Smith’s last-minute request to pause the event, issuing a brief order without any noted dissents just a day ahead of the execution date. Hours later, the 11th U.S. Circuit Court of Appeals followed suit in a 2-1 decision.
Smith’s previous execution attempt was called off in 2022 after officials struggled to secure the needed IV access and poked the inmate with needles for hours.
At least one other inmate’s execution was also called off for a similar reason, and the Yellowhammer State went on to temporarily pause executions as a result.
Smith argued another execution attempt after the first one failed would violate his Eighth Amendment protection against cruel and unusual punishment, while Alabama argued the execution is “perhaps the most humane method of execution ever devised.”
“Such treatment is much better than Smith gave Elizabeth Sennett nearly thirty-six years ago,” state officials told the justices.
Smith is slated to be executed during a 30-hour window between midnight Thursday and 6 a.m. CST Friday, according to multiple media reports. The tentative start time is 6 p.m. Thursday at the William C. Holman Correctional Facility in Atmore, Ala., according to reports.
The Associated Press contributed.