>> the point where i made up my mind that he must be guilty was after i heard his complete testimony, and decided that all of the alibis that he was coming up with were just beyond belief. >> the jury took three hours to find deparvine guilty, and he was sentenced to death. in the end, some saliva on a plastic spoon and a small nick on his hand told investigators how he committed the crime and how he killed two innocent people who were just trying to sell their truck and be on their way. >> i was never really into forensic science or even, you know, gave it any thought. but since that time has happened, i have become hooked on courtv, and i've learned a lot about the way the law works and about the way forensics play