Content warning: This article contains graphic description of an execution
Kenneth Smith has been executed at the age of 58 for his part in the murder-for-hire of a woman in 1988.
Smith and another man murdered Elizabeth Dorlene Sennett after being hired by a man working for her husband, they beat her and stabbed her 10 times in her own home.
Advert
Sentenced to death by the judge at his trial, he spent decades on death row awaiting an execution which was carried out at 8:25pm CST on 25 January.
Smith was pronounced dead 22 minutes after his execution began, and there was some controversy over his sentence being carried out.
The death row inmate is the first person to have been executed by nitrogen hypoxia, where a person is made to breathe nitrogen gas and dies of asphyxiation.
Advert
This method of execution had been challenged by lawyers representing Smith, though the US Supreme Court denied his appeal against it.
A number of medical professionals also challenged the state of Alabama's claims that nitrogen hypoxia was 'perhaps the most humane method of execution ever devised'.
Lawyers for Smith, medical professionals and the UN's High Commissioner for Human Rights voiced concerns that the untested method of execution could amount to torture or inhumane treatment.
An eye-witness to Smith's execution described the details of the death row inmate's final moments, including a graphic account of the minutes he convulsed for on the execution gurney.
Advert
Smith's final meal before execution was a T-bone steak, hash browns, scrambled eggs and toast eaten eight hours before his execution to reduce chances of him vomiting.
In his final words the convicted murderer said: "Tonight, Alabama caused humanity to take a step backward. I am leaving with love, peace and light - thank you for supporting me. I love all of you."
Writing in the Montgomery Advertiser, witness to the execution Marty Roney described Smith's death in some detail, noting that the death row inmate 'appeared to convulse and shake vigorously for about four minutes'.
Advert
Roney noted that the nitrogen gas began being administered at 7:57pm local time and Smith appeared to take his final breath 10 minutes later.
He wrote: "Smith writhed and convulsed on the gurney. He appeared to be fully conscious when the gas began to flow.
"He took deep breaths, his body shaking violently with his eyes rolling in the back of his head. Hood [Rev. Jeff Hood], standing about 15 feet away, made the sign of the cross several times.
"Smith clenched his fists, his legs shook under the tightly tucked-in white sheet that covered him from his neck down. He seemed to be gasping for air. The gurney shook several times during this time. Hood removed his eyeglasses and wiped away tears.
Advert
"Smith appeared to lose consciousness. His chest remained still for about 20 seconds then he took several large gasps for air. There appeared to be saliva or tears on the inside of the facemask. A female witness for Smith sobbed."