Alabama on Thursday executed convicted murderer Kenneth Smith, who held his breath in vain as officials asphyxiated him with nitrogen gas, the first use of a new method of capital punishment since lethal injections began in the U.S. four decades ago.
Smith, convicted of a 1988 murder-for-hire, was a rare prisoner who had already survived one execution attempt. In November 2022, Alabama officials aborted his execution by lethal injection after struggling for hours to insert an intravenous line’s needle in his body.
The state has called its new closely watched protocol “the most painless and humane method of execution known to man.” It predicted Smith would lose consciousness in under a minute and die soon after, although witnesses on Thursday said it appeared to take several minutes longer.
Human rights groups, United Nations torture experts and lawyers for Smith had sought to prevent it, saying the method was risky, experimental and could lead to an agonizing death or non-fatal injury.
In Smith’s second and final trip to the execution chamber on Thursday, executioners restrained him in a gurney and strapped a commercial industrial-safety respirator mask to his face. A canister of pure nitrogen was attached to the mask that, once flowing, deprived him of oxygen.
Before the nitrogen was switched on, Smith made a lengthy final statement that began: “Tonight, Alabama caused humanity to take a step backward.”
His wife and other relatives attended and he gestured towards them. “I’m leaving with love, peace and light,” he said, according to media witnesses. “Love all of you.”
Smith mounted legal challenges in federal courts arguing that Alabama’s new method amounted to unconstitutional “cruel and unusual punishment,” but he failed to cross the high bar needed to have a judge order a delay of his execution.
His lawyers raised fears the mask would not properly seal against Smith’s face, allowing oxygen to seep in, delaying or even averting the moment of unconsciousness but risking serious brain injury.
Though poisonous gases such as hydrogen cyanide have been used in executions in the U.S. and beyond in the past, this was the first time a death sentence was carried out anywhere using an inert gas to suffocate someone, capital punishment experts say.
The U.S. Supreme Court’s conservative majority rejected Smith’s final appeal to delay his death on Thursday evening, and the execution began soon after.
Smith was convicted of murdering Sennett, a preacher’s wife, after he and accomplices each accepted a $1,000 fee from her husband to kill her, according to trial testimony.
Several of Sennett’s relatives attended the execution and told reporters they had forgiven Sennett’s killers.