George Zimmerman, defendant in the killing of Trayvon Martin, is sworn in for testimony in Seminole circuit court during a pre-trial hearing in Sanford, Florida April 30, 2013.
ORLANDO, Fla. — A court hearing begins Tuesday to determine how Trayvon Martin should be portrayed to a jury when a neighborhood watch captain goes on trial for killing the unarmed black teenager last year.
George Zimmerman, whose highly anticipated second-degree murder trial is scheduled to start June 10, has said he shot Martin in self-defense during a fight in February 2012.
At issue in Tuesday's hearing are pieces of evidence that suggest 17-year-old Martin used marijuana at an undetermined time and had been suspended from school shortly prior to his death. The defense also wants to use text messages and social media posts that Zimmerman's lawyer said would show that Martin presented himself as "street wise" and interested in guns.
Prosecutors will argue that the Facebook postings by Martin, who had no criminal record and the way he portrayed himself to his friends is irrelevant to what happened on the night of the killing.
In a motion to ban evidence of marijuana use, prosecutors said there is no evidence that Martin was under the influence or that marijuana contributed to his death. O'Mara claims, however, that the evidence supports the defense theory that Martin was the aggressor.
The hearing before Judge Debra Nelson begins at 9 a.m. EDT (1300 GMT) in the Seminole County Criminal Justice Center in Sanford, where national news media are gearing up for extensive live coverage of the trial.
Zimmerman followed Martin after he spotted him walking in the rain in a gated community in the town of Sanford near Orlando where Martin was spending the weekend in one of the town homes with his father. Zimmerman called police to report a suspicious person and pursued Martin despite the dispatcher telling him not to. Soon after, Zimmerman shot Martin during a struggle before police arrived.
In court filings Zimmerman's lawyers say they want the judge to decide about the use during the trial of voice analysis of 911 tapes of calls to the police before and during the struggle.
Lawyers are seeking clarification from the judge about whether the science behind the various types of voice analysis used by experts for the state and defense is solid enough to be considered by the jury.
Experts have reached different conclusions about whether it was Zimmerman or Martin screaming in the background of a 911 call taped just before Martin was shot, or whether it is possible to be certain at all.
Some experts could isolate only seconds of usable audio on the tape while one prosecution expert claims to have deciphered several phrases uttered by Zimmerman and Martin.
The defense also wants the judge to allow the identities of the jurors to remain secret and to let the jury visit the crime scene.
Martin's death set off debate about Florida's "stand your ground" law, which allows deadly force if a person fears serious bodily harm. Police initially declined to arrest Zimmerman, who is white and Hispanic, which led to racial protests.