The convicted murderer was put to death despite a legal battle over concerns his heart device would repeatedly shock him once the lethal chemicals spread throughout his body.

The Tennessee Supreme Court ruled on July 31 that Byron Black could be executed without deactivating his implanted defibrillator, with the high court noting that requiring that the device be deactivated "amounted to a stay of execution, which is not within the lower court’s power," according to the Associated Press.

Byron Black, a death row inmate with dementia and multiple organ failure, was executed by lethal injection despite having an active heart device his attorneys argued could cause extreme pain. Witnesses say he appeared to suffer during the procedure,