Killen entered the Mississippi Department of Corrections system on June 27, 2005, to serve his sixty-year sentence (three twenty-year sentences running consecutively). That same year, after a circuit court judge denied Killen's request for a new trial, he was sent to the Central Mississippi Correctional Facility (CMCF) in an unincorporated area of Rankin County, near Pearl. He underwent evaluation, and prison officials were deciding whether to keep him at CMCF or to send him to the Mississippi State Penitentiary at Parchman, an unincorporated community in Sunflower County. Killen's release date was September 1, 2027 (by which time he would have been 102 years old). His location last changed on July 29, 2014.