In this Aug. 23, 2011 Defense Video & Imagery Distribution System photo, Army Staff Sgt. Robert Bales, right, participates in an exercise at the National Training Center at Fort Irwin, Calif. Five days after an attack on Afghan villagers killed 16 civilians, a senior U.S. official identified the shooter in that attack as Bales. The man at left is unidentified. (AP Photo/DVIDS, Spc. Ryan Hallock)