An expert in forensic voice identification analyzing the 911 recordings in the Trayvon Martin case for the Orlando Sentinel tells the paper that it is likely not Martin’s shooter, George Zimmerman, heard calling for help.

Tom Owen used voice identification software to rule out Zimmerman, according to the paper. Another expert contacted by the Sentinel, utilizing different techniques, came to the same conclusion.

Zimmerman, a neighborhood watch volunteer, shot Martin, an unarmed 17-year-old, during a confrontation Feb. 26.

On that night, a woman called 911 to report someone crying out for help in her gated Sanford, Fla., community. While several other neighbors also called authorities, the first call came early enough for dispatchers to hear panicked cries and the gunshot that killed Trayvon Martin.

According to the Sentinel, Owen, a court-qualified expert witness, is an authority on biometric voice analysis -- a computerized process comparing attributes of voices to determine whether they match.

"I took all of the screams and put those together, and cut out everything else," Owen said, according to the Sentinel.

Software called Easy Voice Biometrics was used to compare 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 said, stressing that he cannot confirm the voice as Trayvon's because he didn't have a sample of the teen's voice to compare.

Click to read the full story from the Orlando Sentinel