An American man convicted of killing a pastor during a robbery in 1991 was scheduled for execution Thursday in the southeastern state of Alabama.
Christopher Lee Price, 46, and an accomplice were found guilty of stabbing Bill Lynn to death a few days before Christmas that year.
The state plans to put Price to death by lethal injection at a prison in the town of Atmore.
His lawyers filed an appeal against that method of execution, arguing it is cruelly painful. They asked that he be put to death instead by breathing nitrogen gas.
Like a few other states, Alabama approved this latter method in 2018 because of a shortage of chemicals used for lethal injection -- but it has not yet been used.
A federal court on Wednesday turned down Price's request, saying he waited too long to file it. The appeal was then filed with the US Supreme Court.
If that high court does not suspend the execution, it will be the fourth so far this year in the United States.
Price's accomplice is serving a life sentence.