Convicted murderer John Marion Grant, 60, was executed by lethal injection at 4:21 p.m. Thursday inside the Oklahoma State Penitentiary. He was the first Oklahoma inmate to be executed since the practice was halted in 2015 after botched lethal injections. The U.S. Supreme Court allowed the execution to proceed after Grant was given a stay Wednesday by the 10th U.S. Circuit Court of Appeals in Denver.