but they hadn't sent anything related to javier lopez to the crime lab. >> reporter: daron sent javier's samples, now three years old, to the crime lab. two months later, the phone rang. >> they had positively identified a fingerprint on the trunk of cathy's car, left there by somebody closing the lid of the trunk. >> reporter: javier's print was on the trunk of cathy's car? >> yes. >> reporter: weeks later, another call from the lab. a bloodstain on the car had tested positive for both cathy's dna and javier's. and the detective found there was something else -- another major piece of evidence investigators had initially overlooked. >> when you look at the crime scene photos in the trunk of the car, something jumped out at me. and it just -- it hit me like i got punched in the face, was there was arterial spurt on the sidewall of the trunk panel. >> reporter: meaning only one