Chicago (AFP) - Nebraska on Tuesday carried out America's first execution using fentanyl -- the opioid at the center of the country's deadly overdose crisis -- as part of an untested four-drug combination.
Carey Dean Moore, who was sentenced to death for two 1979 murders, was the first prisoner executed in the Midwestern state in 21 years, and the first ever by lethal injection.
Moore was pronounced dead at 10:47 am (1547 GMT) in an execution that lasted approximately 20 minutes, according to Scott Frakes, Director of the Nebraska Department of Correctional Services.
It was a pivotal test for Nebraska, where the state legislature abolished the death penalty in 2015, only to see voters reinstate it the following year in a referendum. It last performed an execution in 1997 with the electric chair.
"I recognize that today's execution impacts many people on many levels," said Frakes, adding that the lethal injection was carried out with "professionalism, respect for the process and dignity for all involved."
Three of the four substances used had never been used for lethal injections -- underscoring the difficulty states across America have had in obtaining previously employed execution drugs.
The protocol consists of the sedative diazepam to render unconsciousness, the painkiller fentanyl citrate, the muscle relaxer cisatracurium to stop an inmate's breathing, and, finally, potassium chloride to stop the heart.
Only potassium chloride has been used before in executions.
Last week, German drug maker Fresenius Kabi challenged Moore's execution in court, believing it had been the source of two of the drugs and contending those were improperly acquired.
The state insisted the drugs were legally obtained and a federal judge on Friday sided with the state. An appellate court also ruled against the German firm on Monday.
- 'I am guilty' -
Moore had been on death row for 38 years and said he did not want further delays.
While still in his early 20s, Moore was sentenced to death in 1980 for the killings of two Omaha taxi drivers five days apart. He admitted to shooting to death the first driver during a robbery committed with his brother.
In his final words, Moore alluded to a written statement dated August 2, in which he pointed to other death row inmates in Nebraska who claim to be innocent.
"I am guilty, they are not," he wrote. "Why must they remain there one day longer?"
Moore also asked forgiveness from his brother.
Moore's was the 16th execution in the US this year, according to the Death Penalty Information Center.