Alabama is seeking to execute a man with lethal injection hours after his nitrogen execution was prevented from going forward.

The U.S. Supreme Court has declined to let Alabama execute a man with nitrogen gas.

A federal judge has permanently blocked Alabama from executing an inmate with nitrogen gas, declaring the method violates the ban on cruel and unusual punishment.

A federal appeals court has ruled that Alabama’s use of nitrogen gas to put prisoners to death needs more study of whether it violates a constitutional ban on cruel and unusual punishment.

A federal judge has ruled Alabama's use of nitrogen gas to carry out executions does not violate the U.S. Constitution.