Deliberations could begin in murder trial of George Zimmerman over death of Trayvon Martin

When jurors begin deliberating in the racially charged murder trial of George Zimmerman, they'll also be able to consider a lesser charge of manslaughter in the fatal shooting of unarmed black teen Trayvon Martin.

The defense, which claims Zimmerman killed Martin in self-defense, will give its closing arguments Friday, a day after the prosecution spent two hours summarizing its case.

Zimmerman is charged with second-degree murder, but the jury will also be allowed to consider manslaughter. But because of the way Florida law imposes sentences for crimes committed with a gun, the lesser charge could also carry a life sentence.

Judge Debra Nelson's ruling to allow consideration of the manslaughter charge came despite the objections of Zimmerman's lawyers.