Updated:SANFORD, Fla. —
George Zimmerman and his attorney requested a hearing to determine the type of expert testimony the jury should be allowed to hear.
Zimmerman is accused of shooting and killing 17-year-old Trayvon Martin in Sanford.
Attorney Mark O'Mara filed the motion on Friday, asking for stricter credentials for anyone identifying a voice in recordings played in court.
It's ultimately up to the jury to determine the credibility of an expert's opinion.
Zimmerman's father told Florida Department of Law Enforcement agents he recognized his son's voice in 911 calls made the night of the shooting, but FBI agents could never confirm it was Zimmerman.