Oklahoma carried out the first execution in the state in six years on Thursday to a death row inmate. John Marion Grant, 60, was executed via lethal injection with a three-drug cocktail. He convulsed and vomited before he was declared unconscious about 15 minutes after the first of three drugs—the sedative midazolam—was administered. He was declared dead about six minutes after that, at 4:21 p.m. Grant was convicted of murder in 1998 for the slaying of a prison cafeteria worker, Gay Carter. At the time, Grant was also serving a 130-year prison sentence for several armed robberies. Witnesses say Grant dragged Carter into a mop closet and stabbed her 16 times with a homemade shank. Grant was sentenced to die in 1999. Carter’s daughter, Pamela Gay Carter, said in a statement, “At least now we are starting to get justice for our loved ones. The death penalty is about protecting any potential future victims. Even after Grant …