Zimmerman's while holding the door for him during a hearing two weeks ago. The friend, Timothy Tucholski, testified that he had n't wanted to make an issue of it before. I was n't planning on coming up here. I do n't want to be sitting here, he said. But Nelson denied the request, and Martin remained in court -- but Zimmerman's parents were covered by the rule regarding potential witnesses and had to sit outside, as did Benjamin Crump, the lawyer for Martin's parents. At one point, Martin's father began crying as Guy detailed how officers tried to save his son's life. Zimmerman has mostly stared straight ahead without any signs of emotion. Following Guy's statement, defense attorney Don West came forward to woo the jury. As he began, he told a knock-knock joke. But it failed to win a laugh. Knock knock. Who's there ? George Zimmerman. George Zimmerman who ? Good, you 're on the jury, he said. Later, West apologized. No more bad jokes, I promise that, he told jurors. I was convinced it was the delivery. West quickly got on with the business of making his case: that Zimmerman was forced to act in self-defense to save his own life. The evidence will show this is a sad case; no monsters here.... George Zimmerman is not guilty of murder. He shot Trayvon Martin after he was viciously attacked. With the help of PowerPoint visuals, West spent hours hammering home his argument. He