Exhibit A: Secrets of Forensic Science

As sophisticated as forensic science has become, the human factor opens the door to fallibility. "Double Jeopardy" presents a tragic example of what happens when forensic science fails. In this case, a forensic scientist misinterprets the facts surrounding a shooting, thereby allowing the guilty party to walk free. But the victim's mother won't let the case rest. Eventually she gathers enough evidence to reopen the case - and prove it was murder. But the murderer can't be tried again because of the laws of "Double Jeopardy."