Records show that one of the drugs that was to be used in Warren Lee Hill's scheduled execution in Georgia last month had expired two weeks before he was scheduled to die.
The Department of Corrections tried to change its procedures from three drugs to one — a barbiturate — in an effort to keep the execution on track.
However, the Georgia Supreme Court issued a stay less than two hours before Hill was to be executed for a 1990 murder.
The Department of Corrections said in a statement Thursday that the unavailability of pancuronium bromide was a factor in the decision to change Georgia's execution protocol, but it was not an "overriding concern."
Hill's execution is now on hold at least until November.