Years her mother kept fighting to find bonnies killer. Bonnies mother continues her own crusade. Then after more than a decade of searching, a phone call. They got information there was a match. Can we get a conviction on just the dna . And there was something else, something about bonnie herself. It was almost like she knew something. Hello and welcome to dateline. We hear about dna evidence to clear the innocent. It seems we hear less about how dna evidence might be used to track down the guilty. This story is about the murder of a young woman whose dna was sent to the National Debate 12 years after she was murdered would turn up a match. But in this case, prosecutors would need more to convict a murderer. Here is keith morrison. Reporter many years ago late on a september night, a family in anchorage, alaska, got a knock on the door. One of those eerie feelings instantly when someone knocks on the door at 10 00 at night and asked to speak to my dad. Reporter 1994, samantha was 12, h