This August 23, 2011 photograph obtained courtesy of the Defense Video & Imagery Distribution System (DVIDS) shows Staff Sgt. Robert Bales (right) at the National Training Center in Fort Irwin, California. (Note at 10:50 p.m. ET: Earlier, we mistakenly said he was on the left.) Spc. Ryan Hallock /AFP/Getty Images hide caption

itoggle caption Spc. Ryan Hallock /AFP/Getty Images

Army Staff Sgt. Robert Bales during an August 2011 training exercise at Fort Irwin, Calif. Spc. Ryan Hallock/AFP/Getty Images hide caption

itoggle caption Spc. Ryan Hallock/AFP/Getty Images

Afghan villagers prayed last week at a ceremony for the 16 victims of what officials say was an attack by a U.S. Army soldier. Allauddin Khan/AP hide caption

itoggle caption Allauddin Khan/AP

Bales joined the military after Sept. 11, 2001. He served three times in Iraq before being deployed to Afghanistan. Courtesy Maj. Brent Clemmer hide caption

itoggle caption Courtesy Maj. Brent Clemmer