Alabama inmate Kenneth Smith executed with nitrogen gas, marking the emergence of a wholly new method of capital punishment

Alabama on Thursday night executed Kenneth Smith, the first death row inmate known to die by nitrogen gas, marking the emergence of a wholly new method of execution in the United States that experts have said could lead to excessive pain or even torture.

Smith, who was sentenced to death for his role in a 1988 murder for hire, had survived the state’s initial attempt to execute him by lethal injection in 2022. Earlier Thursday, the US Supreme Court denied his last-minute appeal to halt the execution, after declining the same request on Wednesday.

Smith’s time of death was 8:25 p.m. local time, officials announced. In a news conference after the execution, Alabama Department of Corrections Commissioner John Hamm said nitrogen was running for about 15 minutes.

In a joint report, witnesses from the media said Smith made a lengthy statement before he died, saying, “Tonight Alabama caused humanity to take a step backward,” and adding, “I’m leaving with love, peace and light, thank you for supporting me, love all of you.”

Smith appeared conscious for “several minutes into the execution,” and for two minutes after that, he “shook and writhed on a gurney,” according to the media witness report. That was followed by several minutes of deep breathing before his breath began slowing “until it was no longer perceptible for media witnesses.”

When asked at the news conference about Smith shaking during the start of the execution, Hamm said Smith appeared to be holding his breath “for as long as he could” and may have also “struggled against his restraints.”

“There was some involuntary movement and some agonal breathing, so that was all expected and is in the side effects that we’ve seen and researched on nitrogen hypoxia,” Hamm added. “So nothing was out of the ordinary of what we were expecting.” Agonal breathing is usually described as a kind of gasping seen in people who are dying.

Another witness, Smith’s spiritual adviser who’d previously expressed concern that the method could be inhumane, described the death in more graphic terms, saying it was “the most horrible thing I’ve ever seen.”

Smith, wearing a mask through which the nitrogen was administered, convulsed when the gas was turned on, “popped up on the gurney” repeatedly, and gasped and heaved, the Rev. Jeff Hood said.

“An unbelievable evil was unleashed tonight,” Hood said.

One of the sons of the victim, Elizabeth Sennett, said Smith’s death got justice for his mother.

“Nothing happened here today that’s going to bring mom back. Nothing,” Mike Sennett said at the news conference. “We’re glad this day is over. All three of the people involved in this case years ago, we have forgiven them.”

“Kenneth Smith made some bad decisions 35 years ago, and his debt was paid tonight,” he said.

In a statement, Smith’s legal team said they were “deeply saddened” by his death, adding he had found and “sincerely practiced his faith,” had become sober and helped other inmates achieve sobriety, and had earned an associate’s degree.

“Nothing can undo the tragic consequences of the actions for which he was convicted, including the pain of the Sennett family and friends. Kenny’s life, however, should be considered in its full context,” the statement added.

Little is known about how the method of execution, known as nitrogen hypoxia, was carried out because the state’s published protocol bears redactions experts say shield key details from public scrutiny. The state, in court records, indicated the redactions were made to maintain security and it believes death by nitrogen gas to be “perhaps the most humane method of execution ever devised.”

But Smith and his team were skeptical. “The eyes of the world are on this impending moral apocalypse,” the inmate and his spiritual adviser, Hood , said midday Thursday in a joint statement. “Our prayer is that people will not turn their heads. We simply cannot normalize the suffocation of each other.”

Elizabeth Sennett’s sons told CNN earlier Thursday they felt it was time for Smith’s sentence to be carried out, adding they believed their mother was forgotten because of the new execution method.

“It seems like a lot of the focus today is on Smith and his nitrogen, whatever, process,” Mike Sennett said. “And that’s kind of upset us a little bit.”

“What’s going on is overshadowing what’s actually happened,” his brother, Chuck Sennett, said. “He’s gotta pay the price for what he done to our mother,” who should be remembered “as a loving, caring woman.” The two brothers were in their 20s when their mother was killed.

Before his execution, Smith accepted a final meal of steak, hashbrowns and eggs, according to information released by the Alabama Department of Corrections.

Only 3 states have approved nitrogen for executions

The US Supreme Court first declined to intervene in Smith’s case on Wednesday after his attorneys tried to argue a second execution attempt would violate the US Constitution’s protection against cruel and unusual punishment.

A separate federal appeals court ruling on Wednesday evening also declined to halt the execution . Smith’s team had again appealed Thursday morning to the Supreme Court.

State officials on Wednesday welcomed the high court’s rejection of Smith’s earlier request, framing it as an “attempt to bar the State from executing him by any method at all,” Attorney General Steve Marshall said in a statement.

Alabama “remains confident that the execution, and long-awaited justice, will proceed as planned,” he said.

Still, Smith’s advocates and critics of the state feared the nitrogen gas execution could go awry, pointing to its novel nature, questions around its shrouded protocol and Alabama’s recent struggles to carry out lethal injections.

In 2022 alone, the state carried out or attempted three executions in a row that critics deemed “botches,” meaning they deviated from the stated protocol. In two of the cases, the inmates – including Smith – survived as officials called off the executions because they could not set an intravenous line used to deliver the fatal drugs before the death warrants expired.

Alabama on Thursday used nitrogen hypoxia, a method it adopted in 2018. It is one of just three states, along with Oklahoma and Mississippi, that has approved the use of nitrogen for executions, though no other state has used it and only Alabama has a protocol.

In theory, the method involves replacing the air breathed by an inmate with 100% nitrogen, depriving the body of oxygen. Its proponents contend the process will be painless, citing nitrogen’s role in deadly industrial accidents or suicides.

Others are skeptical, including a group of United Nations experts who this month voiced concern a nitrogen gas execution will “result in a painful and humiliating death,” with no scientific evidence to the contrary.

Kenneth Smith, left, poses Monday with his spiritual adviser, the Rev. Jeff Hood. - Courtesy Rev. Jeff Hood
Kenneth Smith, left, poses Monday with his spiritual adviser, the Rev. Jeff Hood. - Courtesy Rev. Jeff Hood

“It’s lunacy, absolute lunacy,” Smith’s spiritual adviser said before the execution.

“The process, obviously, is designed to execute Kenneth Smith,” Hood told CNN. “But the way that they’re constructing this, the way that they’re doing it, the way that they’re being silent, the way that they’re holding back information, yes, it’s incredibly concerning. And should be incredibly concerning for everybody in the room.”

Apart from the execution method, Smith’s life should be spared based on the previous, failed attempt to put him to death, said the founder and director of the Equal Justice Initiative, a non-profit opposed to excessive criminal punishment that advocates on behalf of death row inmates. The group has assisted Smith’s attorneys in the case.

“Since that time, we’ve been arguing that the state doesn’t have the competency to carry out these executions,” Bryan Stevenson told CNN on Thursday. “They switched the method, and now they’re saying they have the skill to carry out a method that’s untested and never been used before.”

Smith’s jury voted 11-1 for life sentence

Smith was convicted and sentenced to death for the murder of Sennett, whose husband, Charles, was having an affair and had taken out an insurance policy on his wife, according to court records.

Charles Sennett recruited a man who recruited two others, including Smith, and agreed to pay each $1,000 to kill his wife and make it look like she died in a burglary, the records show. The men carried out the killing as planned in March 1988, and Smith took from the Sennett home a VCR player that he stored in his own home.

Charles Sennett killed himself a week after the murder, records state, as the investigation’s focus turned to him. Smith was ultimately arrested after authorities, based on an anonymous tip, searched his home and found the VCR player.

Smith was convicted and sentenced to die, but an appeals court overturned the initial outcome and ordered a new trial. He was again convicted in the retrial, but this time his jury voted 11-1 for a sentence of life in prison without the possibility of parole.

The judge in Smith’s second trial, however, essentially vetoed the jury’s vote and sentenced the defendant to death – a practice known as judicial override that’s since been repealed in Alabama.

CNN’s Devan Cole, Chris Youd, Olivia LaBorde, Jamiel Lynch and Alta Spells contributed to this report.

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