Alabama is looking to use the nitrogen hypoxia execution method for the second time after the new method was used last month on death row inmate Kenneth Eugene Smith.

Smith, who was convicted of stabbing a woman to death in 1988 in a murder-for-hire scheme, was strapped to a gurney and exposed to nitrogen gas through a tube and into a mask. Smith’s spiritual adviser, the Rev. Jeff Hood, witnessed his death and said he convulsed and “popped up” on the gurney during the 22-minute execution.