SANFORD, Fla. (AP) - An expert hired by an Orlando newspaper testified Friday that screams for help on 911 calls don't match neighborhood watch volunteer George Zimmerman's voice.
Tom Owen testified on the second day of a hearing that will determine whether voice identification experts can be used at Zimmerman's second-degree trial for fatally shooting 17-year-old Trayvon Martin. The trial starts Monday and Zimmerman is pleading not guilty, claiming self-defense.
Testimony for the hearing was to continue Saturday before Circuit Judge Debra Nelson makes a decision.
Owen was hired by the Orlando Sentinel last year to compare a voice sample of Zimmerman with screams for help captured on 911 calls made by neighbors. He said Zimmerman's voice doesn't match the screams. He only compared Zimmerman's voice to the 911 calls because he didn't have a voice sample for Martin at the time.
"The screams don't match at all," Owen said. "That's what tells me the screams aren't George Zimmerman."
Owen also testified that remarks Zimmerman made in a conversation with a police dispatcher aren't a racial slur. He testified Zimmerman said, "These f------ punks."
Under questioning from Zimmerman's attorney, Owens conceded that the sample wasn't long enough to run a proper test according to the specifications of the software. He said he "looped" - or repeated the sample - in order to run the analysis. Defense attorney Don West said that was a novel technique and went against usual standards.
Nelson has said the standard for determining whether technology under question is allowed at trial is whether it is too novel or not accepted by a community of experts.
Owen also conceded he had a financial interest in the software he used to conduct the analysis.
An audio expert also gave testimony Friday by telephone. Alan Reich has said in a report for prosecutors that the screams on the 911 tapes were from Martin and the defense does not want him to testify at trial.
Reich's analysis also picked up words that other experts never found. They include the words, "This shall be" from Zimmerman and "I'm begging you" from Martin, according to Reich.
Under cross-examination, though, Reich said it wasn't possible to reach absolute conclusions based on the quality of the audio.
An FBI expert testified a day earlier that there wasn't enough clear sound on the 911 recordings to determine whose voice it was. Hirotaka Nakasone also said the concept that individuals have unique voice-prints that identify them is misleading. "No one can speak in the same way twice," Nakasone said.
The screams captured on the 911 calls are crucial pieces of evidence since they could determine who the aggressor was in the confrontation. Martin's family contends it was the teen screaming, while Zimmerman's father has said it was his son.
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