Trayvon Martin: Shouts for help heard on a 911 recording may be Trayvon Martin's or may be George Zimmerman's. Audio experts disagree on the source of the shouts.
Attorneys prosecuting Zimmerman on a charge of second-degree murder hired the audio experts to compare samples of Zimmerman's and Martin's voices with the shouts from the 911 calls phoned in by neighbors of Zimmerman. The residents of the gated community heard the neighborhood watch leader struggling with the South Florida teen during a confrontation last year. Determining whose voice was calling for help could aid a jury in deciding whether Zimmerman's claims of self-defense were justified.