George Zimmerman, a neighborhood watch volunteer in Sanford, Fla., who shot unarmed 17-year-old Trayvon Martin on Feb. 26, 2012, is seen at left in booking photo provided by the Orange County Jail via the Miami Herald following a 2005 arrest, and at right in an undated but recent photo of Zimmerman taken from the Orlando Sentinel's website. (Associated Press)

George Zimmerman, a neighborhood watch volunteer in Sanford, Fla., who shot unarmed 17-year-old Trayvon Martin on Feb. 26, 2012, is seen at left in booking photo provided by the Orange County Jail via the Miami Herald following a 2005 arrest, and at right in an undated but recent photo of Zimmerman taken from the Orlando Sentinel's website. (Associated Press)