By Daily Mail Reporter and James Nye PUBLISHED: 11:21 EST, 7 June 2013 | UPDATED: 14:22 EST, 7 June 2013 An independent audio expert believes that George Zimmerman is most likely the harrowing voice screaming for help in the crucial 911 call made seconds before Trayvon Martin was shot dead. As attorney's convene back in court in Florida today to continue a hearing to determine whether jurors will even listen to the phone call - this new revelation significantly bolsters Zimmerman's claim of self-defense. ABC News exclusively obtained a sample of the distressing emergency call - which could prove pivotal once the trial of 29-year-old Zimmerman begins - and sent it to Kent Gibson of Forensic Audio.
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Exclusive ABC News evaluation reveals that the voice heard screaming for help on 911 call is George Zimmerman and not Trayvon Martin
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Attorney had yesterday requested confidential testimony as some witnesses said they were concerned for their safety
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But judge rejected request after arguments from media and prosecutors
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Zimmerman's trial for 2012 murder of Trayvon Martin starts next week
The information includes @placeholder possibly holding a gun and smoking marijuana.