Alabama Set to Carry Out First U.S. Execution by Nitrogen

Alabama is set to carry out the first American execution using nitrogen gas on Thursday evening, potentially opening a new frontier in how states execute death row prisoners despite concerns from death penalty opponents about the untested method.

Several courts, including the U.S. Supreme Court, have allowed the execution to move forward, though lawyers for the condemned prisoner, Kenneth Smith, are making one more last-minute request for the nation’s top court to intervene.

As it stands, prison officials plan to begin the execution around 6 p.m. Central time. Mr. Smith, 58, is one of three men convicted in the 1988 murder of a woman whose husband, a pastor, had recruited them to kill her.

The protocol released by prison officials calls for strapping Mr. Smith to a gurney in the state’s execution chamber in Atmore, Ala., after which a mask will be placed on his head and a flow of nitrogen will be released into it, depriving him of oxygen. It would be the second time the state has tried to kill Mr. Smith, after a failed lethal injection in November 2022 in which executioners could not find a suitable vein before his death warrant expired.

The nitrogen method is similar to that used in some assisted suicides in Europe and elsewhere. Lawyers for the state have argued that death by nitrogen hypoxia, as it is known, is painless, with unconsciousness occurring in a matter of seconds, followed by stoppage of the heart. They also note that Mr. Smith and his lawyers have themselves identified the method as preferable to the troubled practice of lethal injection in the state.

Mr. Smith’s lawyers contend that Alabama is not adequately prepared to carry out the execution, that a mask — rather than a bag or other enclosure — could allow in enough oxygen to prolong the process and cause Mr. Smith to suffer, and that Mr. Smith, who has lately experienced frequent nausea, could choke under the mask if he vomits.