Alan Eugene Miller was executed in Alabama by Nitrogen hypoxia on Thursday. He became the second inmate after Kenneth Smith to die by this method.
The 59-year-old Miller was sentenced to death in 2000 for the 1999 murders of three men.
His time of death was recorded at 6:38 pm at a prison in Atmore, according to Alabama Department of Corrections Commissioner John Hamm.
Witnesses said that Miller shook and trembled on the gurney for about two minutes, with his body occasionally pulling against the restraints.
This was followed by approximately six minutes of sporadic gulping breaths before he became still.
According to Hamm, during the execution Nitrogen gas flowed for 15 minutes, and two minutes of shaking was because Nitrogen depleted the Oxygen of the body.
He said, “Everything went according to plan and according to our protocol, so it went just as we had planned.”
“I didn’t do anything to be in here,” Miller said in his final words, which at times were muffled by a mask that covered his face from forehead to chin, according to the AP.
Alabama Governor Kay Ivey said, “Tonight, justice was finally served for these three victims through the execution method elected by the inmate.”
“His acts were not that of insanity, but pure evil. Three families were forever changed by his heinous crimes, and I pray that they can find comfort all these years later,” he added.
The execution came after a complicated history of Miller’s death sentence.
Miller was scheduled for lethal injection after the US Supreme Court lifted a lower court’s order in a dispute over his execution method. He preferred nitrogen hypoxia, as it was believed to be a painless option, over lethal injection.
In September 2022, Alabama attempted to execute him by lethal injection but failed to find suitable veins.
The United Nations experts condemned the use of nitrogen gas for executions, labelling it “State-sanctioned torture,” calling its use on humans “outrageous.”
Although Alabama is the only state to have attempted this method, Louisiana, Oklahoma, and Mississippi have also authorised nitrogen hypoxia for executions.
Experts warn that nitrogen hypoxia may cause severe suffering, despite being promoted as a painless method of execution by depriving the body of oxygen.