The Supreme Court declined to intervene to stop Alabama from using nitrogen gas to execute a death row inmate, allowing for the execution to be carried out using the method Thursday for the first time in the United States.

In a brief order issued Wednesday without any noted dissents, the justices rejected Kenneth Eugene Smith’s last-minute request to pause his execution.

Smith has separately asked the 11th U.S. Circuit Court of Appeals to put his execution on hold, and that court has not yet issued a ruling.

Smith was placed on death row after a jury convicted him of capital murder over a murder-for-hire plot in 1988 in which Smith and an accomplice killed a preacher’s wife by stabbing her 10 times.

“Kenneth Smith is scheduled to be executed by nitrogen hypoxia, perhaps the most humane method of execution ever devised. Such treatment is much better than Smith gave Elizabeth Sennett nearly thirty-six years ago,” Alabama told the justices.

Alabama is seeking to carry out the first execution nationwide using nitrogen hypoxia after Smith’s previous execution attempt was called off in 2022.

During that attempt, which similarly followed last-minute litigation, officials had difficulty securing the needed IV access, poking Smith with needles for hours.

At least one other inmate’s execution was previously called off for similar reasons, and Alabama eventually paused executions in the state as a result.

Smith had contended subjecting him to an execution attempt after the botched one would violate his Eighth Amendment protection against cruel and unusual punishment, also saying the method was untested.

“States have failed at executions before. But upon information and belief, if Alabama proceeds with its planned execution attempt, it will be only the second time in U.S. history that a state follows through with a second execution attempt after a previous, failed attempt,” Smith’s lawyers wrote in court filings.

But Alabama’s Republican-controlled attorney general’s office urged the Supreme Court to allow the state to move forward with its planned execution, pushing back on Smith’s Eighth Amendment claim.

“Smith and an accomplice tricked Elizabeth into letting them into her home, only to stab her eight times in the chest and twice in the neck—all to make a quick buck. Now Smith says his execution will be cruel and unusual because fourteen months ago, he was ‘stabbed’ … with a needle to obtain IV access during a prior execution attempt,” the state wrote in court filings.

Scheduled executions often result in last-minute emergency litigation at the Supreme Court, and the conservative-majority bench in most recent cases has declined to grant inmate requests for pauses.