that mexico is going to find, catch and adjudicate the killers in what is a lawless part of mexico? >> i really cannot answer that, but i can tell you that, based on past record, i think they have somewhat of a zero solvency rate and zero conviction rate. >> reporter: there is one more piece of evidence. a small blood spot on the life jacket tiffany hartley wore the day she says her husband was shot. the blood is from her husband. sheriff gonzalez says a dna test confirms it, but even the dna match remains just one more piece of an unsolved puzzle. there is still no body, no jet ski. is tiffany hartley even telling the truth? or is there another secret yet to be told? [ female announcer ] thanks for financing my first car. thanks for giving me your smile.