"Do not get close to anybody," O'Brien said of what he understood about neighborhood watch. "Stay at a safe distance and call 911. Let the police handle it."
The prosecution began opening statements Monday in the long-awaited murder trial with shocking language, repeating obscenities Zimmerman uttered while talking to a police dispatcher moments before the deadly confrontation.
The defense opened with a knock-knock joke about the difficulty of picking a jury for a case that stirred nationwide debate over racial profiling, vigilantism and Florida's expansive laws on the use of deadly force.
Guy portrayed the then-neighborhood watch volunteer as a vigilante, saying, "Zimmerman thought it was his right to rid his neighborhood of anyone who did not belong."
Defense attorney Don West told jurors a different story: Martin sucker-punched Zimmerman and then pounded his head against the concrete sidewalk, and that's when Zimmerman opened fire.