Lee’s lawyers asked the high court to keep the execution on hold, saying in a response that Alabama was asking it to intervene at the eleventh hour “to allow an execution that has been found unconstitutional to proceed”

Jeffery Lee faces execution Thursday because a judge overturned a jury’s vote for a life sentence under a since-abolished procedure called judicial override.

A federal appeals court says Alabama's use of nitrogen gas for executions needs more study to see if it violates the constitutional ban on cruel and unusual punishment