and this is dateline. i can t believe that their baby is lying there lifeless. she was everything to me. she was so sweet everybody. state troopers said bonnie had died in a hiking accident. the said she fell off a cliff. her mother said, they were wrong. i was screaming to them, these are defensive wounds. no witnesses, no weapon. nothing left behind by a stranger s dna. we no longer have some accidental death. this was a homicide. they had no suspect. but for years, her mother kept fighting to find bonnie s killer. bonnie s mother continues her own crusade. then after more than a decade of searching, a phone call. i just 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 often see headlines about dna evidence exonerating the innocent. it seems we hear less about how dna from an unknow