Defense attorney Mark O'Mara, in a motion, asked the judge to conduct a hearing and listen to evidence about how the experts did their work then decide whether to allow them to testify at the trial of George Zimmerman, charged with shooting Trayvon Martin, an unarmed black teenager, in Sanford last year, the Orlando (Fla.) Sentinel reported Monday.
The motion, filed Friday but made public Monday, most likely was related to a 911 recording made Feb. 26, 2012, the night Zimmerman killed Martin, the report said.
Zimmerman has maintained he is innocent because of Florida's stand your ground laws.
The Sentinel said a neighbor called police to report a fight outside. During the call, a voice in the background can be heard crying for help, then 40 seconds later, a loud bang is heard then the crying ceased.
Zimmerman told police he was the one screaming for help because Martin was beating him. Martin's parents said the screams were from their son, although, his father initially told Sanford police they were not.
O'Mara's motion does not identify the experts he's challenging. The Sentinel said it had two audio experts analyze the voice on the tape last year and both concluded it was not Zimmerman. Prosecutors included the experts -- Tom Owen, chairman emeritus of the American Board of Recorded Evidence, and Ed Primeau, an audio engineer from Rochester Hills, Mich. -- on their witness list.
Zimmerman's second-degree murder trial in Sanford begins June 10.
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