Jurors in the trial of George Zimmerman heard closing arguments from his defense day. Defense attorney Mark O’Mara hopes to convince the panel that the shooting of 17-year-old Trayvon Martin was an act of self-defense, not a murder, says the Orlando Sentinel. O’Mara is making the case that none of the witnesses who live in the townhome community where Trayvon was shot said Zimmerman was an overzealous “cop wannabe.” Zimmerman, 29, faces up to life in prison if convicted of second-degree murder, the most serious charge. He could also face up to 30 years in prison if convicted on manslaughter, a lesser charge jurors will consider. In the state’s closing, prosecutor Bernie de la Rionda told jurors Zimmerman was a “wannabe cop,” tired of crime in his community, who decided he was going to “take care of it” when he spotted Trayvon Feb. 26, 2012. “A teenager is dead,” de la Rionda began, “because a man made certain assumptions…and because his assumptions were wrong, Trayvon Benjamin Martin no longer walks on this Earth.”