Tennessee officials must deactivate a death-row inmate 's implanted heart-regulating device to avert the risk that it might try to shock him during his lethal injection, a judge ruled Friday. The order by Nashville Chancellor Russell Perkins comes ahead of the Aug. 5 execution of Byron Black. Black's attorneys have said that the implantable cardioverter-defibrillator could shock him in an attempt to restore his heart's normal rhythm after the single dose of pentobarbital, with the potential for multiple rounds of shocks and extreme pain and suffering.