(CBS) SANFORD, Fla. - The voice heard calling for help on a 911 call just before Trayvon Martin was fatally shot was not that of George Zimmerman, two forensic voice identification experts told MSNBC on Sunday.
"The tests concluded that it's not the voice of Mr. Zimmerman," Tom Owen, of Owen Forensic Services LLC and chair emeritus for the American Board of Recorded Evidence said.
When asked if he thought such tests would be admissible in court, Owen said "yes" and noted he had recently used similar testing at a murder trial that involved a 911 call.
The conclusions of Owen and another audio expert were first reported by The Orlando Sentinel on Saturday.
The 911 call he examined came in on the night of Feb. 26 from a woman who reported someone crying out for help in a gated community in Sanford, Fla. In the recording of her 911 call, panicked cries and a gunshot are heard.
After the Sentinel contacted Owen, he used software called Easy Voice Biometrics to compare Zimmerman's voice to the 911 call screams.
"I took all of the screams and put those together, and cut out everything else," Owen says.
The software compared that audio to Zimmerman's voice. It returned a 48 percent match. Owen said to reach a positive match with audio of this quality, he'd expect higher than 90 percent.
"As a result of that, you can say with reasonable scientific certainty that it's not Zimmerman," Owen says, stressing that he cannot confirm the voice as Trayvon's, because he didn't have a sample of the teen's voice to compare.
The Sentinel said that Ed Primeau, a Michigan-based audio engineer and forensics expert, came to the same conclusion.
"I believe that's Trayvon Martin in the background, without a doubt," Primeau says, stressing that the tone of the voice is a giveaway. "That's a young man screaming."