Alabama inmate Kenneth Smith put to death in first U.S. nitrogen gas execution

An Alabama man was put to death using nitrogen gas Thursday evening in a first-of-its-kind execution that could influence states in pursuit of a viable alternative to lethal injection.

Kenneth Eugene Smith, 58, was executed by nitrogen hypoxia, in which he was strapped to a gurney and made to breathe nitrogen gas through a mask apparatus, depriving him of oxygen, prison officials at the William C. Holman Correctional Facility in Atmore said. The execution started at 7:53 p.m. local time, and Smith’s time of death was 8:25 p.m., according to corrections officials, who added that the nitrogen was flowing for about 15 minutes.

“Tonight, Alabama caused humanity to take a step backward,” Smith said in his last words, according to media witnesses.

“I’m leaving with love, peace and light,” he added. “Thank you for supporting me, love all of you.”

Media witnesses said he appeared conscious for several minutes into the execution, and then he appeared to shake and writhe on the gurney for two minutes. That was followed by several minutes of deep breaths until his breathing slowed and it was no longer perceptible to media witnesses.