A prisoner in Alabama has become the first inmate in the world to be executed with nitrogen gas.
Convicted murderer Kenneth Smith was put to death after the US Supreme Court declined his legal bid to halt his execution.
His official time of death was recorded at 8.25pm on Thursday evening local time (2.25am Friday, UK GMT).
According to official witnesses, the execution took about 22 minutes and Smith appeared to remain conscious for several minutes. For at least two minutes, he appeared to shake and writhe on the gurney, sometimes pulling against the restraints.
That was followed by several minutes of heavy breathing, until breathing was no longer perceptible.
In a final statement, Smith said: “Tonight Alabama causes humanity to take a step backwards… I’m leaving with love, peace and light.”
He made the ‘I love you sign’ with his hands toward family members who were witnesses. “Thank you for supporting me. Love, love all of you,” Smith said.
A humane death or a lethal experiment? How Alabama’s controversial nitrogen execution works
In a statement Alabama state governor Kay Ivey said: “On March 18, 1988, 45-year-old Elizabeth Sennett’s life was brutally taken from her by Kenneth Eugene Smith.
“After more than 30 years and attempt after attempt to game the system, Mr Smith has answered for his horrendous crimes.
“The execution was lawfully carried out by nitrogen hypoxia, the method previously requested by Mr Smith as an alternative to lethal injection.
“At long last, Mr Smith got what he asked for, and this case can finally be put to rest.
“I pray that Elizabeth Sennett’s family can receive closure after all these years dealing with that great loss.”
The Alabama attorney general Steve Marshall said: “Alabama has achieved something historic. Like most states, Alabama has made the judgement that some crimes are so horrific that they warrant the ultimate penalty.
“But anti-death-penalty activists have worked to nullify that moral judgement through pressure campaigns against anyone assisting states in the process.
“They don’t care that Alabama’s new method is humane and effective, because they know it is also easy to carry out.”
The use of nitrogen gas as a method of execution is highly controversial and had never been used before in the world.
It involves clamping a mask tightly to the face, covering the mouth and nose. The mask is then fed with nitrogen gas. The person continues to breathe normally, but with no oxygen present the body gradually shuts down until death occurs – effectively they are suffocated.
Smith’s execution comes after he survived a botched lethal injection in 2022 which helped prompt a review of the state’s death penalty procedures.
The Supreme Court justices declined to uphold Smith’s legal challenge that claimed a second execution attempt by Alabama – after the first failure caused him severe trauma – would violate the US Constitution’s 8th Amendment protections against cruel and unusual punishment.
However the decision was not unanimous, with three justices voting to halt the execution.
“Having failed to kill Smith on its first attempt, Alabama has selected him as its ‘guinea pig’ to test a method of
execution never attempted before,” Justice Sonia Sotomayor wrote, saying she would have granted the injunction.
“The world is watching.”
Just minutes before the execution was carried out, the Supreme Court refused for a second time to intervene to stop it going ahead.
