And an onair spanking. How samuel l. Jackson reacted when he believed he was mistaken for another black actor. A whats in your wallet black guy. Well show you a live and very public lesson that one anchorman will never forget. No question about that. Keep it right here, america. Nightline is back in just 60 seconds. Good evening. Today the defense started presenting its case in a murder trial that contains a combustible mix of race and guns and is playing out in the same state where Trayvon Martin died, florida. The accused is a 47yearold white Software Developer named michael dunn. The victim, an apparently unarmed black 17yearold named jordan davis. The alleged motive . Loud rap music. Abcs ryan owens is on the story for our series crime and punishment. Reporter is it possible this rap song could be a motive for murder . Infrared, yeah, we love them possible that a 17yearold is dead because he wouldnt turn down the volume . Thats the stunning accusation of prosecutors in the state of