In Montgomery, Alabama, a federal judge heard testimonies on Tuesday about the nation's first two nitrogen gas executions after lawyers for death row inmate Carey Dale Grayson asked for an injunction to halt his execution.

Carey Dale Grayson, 49, is set to die on Nov. 21. He would be the third Alabama inmate to die this year using nitrogen gas.

Lawyers for death row inmate Carey Dale Grayson are attempting to block his coming execution by nitrogen hypoxia.

Justice activist groups are leading a panel discussion about the impact of the death penalty in Alabama. This comes as a federal judge is deciding whether to allow the State to use nitrogen hypoxia again next month to put an inmate to death,

A federal judge is hearing testimony about the nation’s first two nitrogen gas executions, weighing whether to let Alabama carry out a third such execution next month.

The state said Alan Miller’s execution by lethal gas would be “more humane.” He writhed and gasped for air in his final moments.

Alan Eugene Miller, who was put to death on Thursday, was convicted of killing three people during a 1999 workplace shooting spree.