Death row inmate Kenneth Smith has been executed using a new method of nitrogen hypoxia.
On 25 January, Smith was executed at 8.25pm CST (02.25am GMT) at Holman Correctional Facility, Alabama.
Along with colleague John Forrest Parker, Smith was convicted of the murder-for-hire of Alamaba woman Elizabeth Dorlene Sennett in 1988.
Sennett's husband had hired a man to murder his wife, who in turn had hired Smith and Parker.
She was stabbed 10 times in her home, suffering eight wounds to the chest and two to the neck which proved to be fatal.
A week after Elizabeth's murder her husband, Charles Sennett Sr, took his own life after learning he was a suspect in her killing.
Parker was sentenced to death and executed by lethal injection in 2010, while Smith had been scheduled for execution in 2022 but managed to survive it as the execution team could not connect an intravenous line for a lethal injection before his death warrant expired.
After nitrogen gas was selected as a new method of execution, lawyers representing Smith claimed that it would violate his rights under the Eighth Amendment of the US Constitution, which protects people against 'cruel and unusual' punishments.
However, the US Supreme Court on Wednesday (24 January) declined to hear Smith's appeal and denied the death row inmate's request to halt the execution.
Smith's execution successfully went ahead last night, with the inmate being pronounced dead by officials 22 minutes after it began at 8.25pm CST.
In a final statement, Smith said: "Tonight Alabama causes humanity to take a step backwards. … I’m leaving with love, peace and light."
He then made the 'I love you sign' with his hands toward family members who were present, saying: "Thank you for supporting me. Love, love all of you."
Despite Alabama claiming that the nitrogen method was 'perhaps the most humane method of execution ever devised', eyewitness statements from reporters present in the death chamber suggested that this was not the case.
Marty Roney of the Montgomery Advertiser reported that at one point, "Smith writhed and convulsed on the gurney. He took deep breaths, his body shaking violently with his eyes rolling in the back of his head."
Roney went on: "Smith clenched his fists, his legs shook … He seemed to be gasping for air. The gurney shook several times."
According to the Death Penalty Information Center, nitrogen hypoxia is the first of its kind anywhere in the world.
Execution via nitrogen gas is a controversial procedure, as ethical questions have been raised on using the untested method of execution.
Nitrogen hypoxia is a form of execution where a person is deprived of oxygen until they are breathing only nitrogen gas, killing them via asphyxiation.
Already making up around 80 percent of the air we breathe, nitrogen is not lethal unless separated from oxygen.
The State of Alabama said in court filings that with the execution method they expect a person to lose consciousness within seconds and die within minutes, though a number of medical professionals have contested this claim.
There are dangers associated with using nitrogen gas as a method of execution as Joel Zivot, Emory University's School of Medicine Associate Professor in anaesthesiology told USA Today.
He said that execution via nitrogen hypoxia was a method that could cause a seizure, causing the person being put to death to vomit and die from choking instead.
The UN's High Commissioner for Human Rights also voiced opposition to the execution method, saying it could amount to torture or inhumane treatment.
Featured Image Credit: Alabama Department of Corrections/Getty Stock Image