George Zimmerman talks to his attorney Mark O'Mara, right, during a recess in Seminole circuit court during Zimmerman's trial in Sanford, Fla., Monday, June 17, 2013. Zimmerman has been charged with second-degree murder for the 2012 shooting death of Trayvon Martin. He has plead not guilty to the charges. (AP Photo/Orlando Sentinel, Joe Burbank, Pool)

911 call debated at Zimmerman trial

Kyle Hightower and Mike Schneider, Associated Press
SANFORD, Fla. (AP) — A voice recognition researcher for George Zimmerman is discounting the methods of prosecution experts who claim that screams captured on a 911 call belong to 17-year-old Trayvon Martin and not to the ex-neighborhood watch volunteer...