Transcript for George Zimmerman Trial Gets Under Way
And to florida this evening, where the trial of george zimmerman is set to begin. Zimmerman, the neighborhood watchman, accused of murdering trayvon martin. Opening statements begin tomorrow morning. And tonight here, three major questions. How long is it expected to last? Will george zimmerman take the stand in his own defense? And how crucial will that 911 call be, those cries heard on tape, in deciding his fate? Abc's byron pitts is in sanford, florida, for us tonight. Reporter: It's the case that's renewed america's long, bitter and polarizing debate over both race and guns. Neighborhood watchman george zimmerman now facing trial for second degree murder in the death of 17-year-old trayvon mar martin. The jury of six women will be sequestered during the trial, which is expected to last two to four weeks. Those jurors will hear from key witnesses, neighbors who saw or heard the fight that fateful night. The jury will also watch that video clip of zimmerman describing how he acted in self-defense. But will he take the stand? His lawyer says he'll make that decision during the trial. One of the toughest jobs for the jury, determining who was crying out for help on that 911 call. prosecutors have argued it's martin's voice, with voice experts to back that up. But zimmer mapp's lawyers cou count countered, saying it was his voice. The case may hinge on whose voice is on that call. In a last-minute ruling, the judge included jurors would hear from the prosecution voice experts. Why is that considered a setback for the prosecution? Because the prosecution wants their expert to testify that it's trayvon martin's voice we hear. Why? Because there's this phenomenon of listener expectation or listener bias. That is, if you're told you're going to hear something, you're likely to hear it, whether it's there or not. Reporter: If convicted, george zimmerman could face life in prison, though few expect him to receive the maximum penalty if he were found guilty.
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