20. Jean Pool

In 1984, the body of college co-ed Laura Salmon was found on a Georgia farm, covered with her own denim jeans as well as the jeans of the killer. Investigators had plenty of suspects, including former boyfriend David Kyle Gilley, but no conclusive evidence linking any of them to the crime. More than a decade later, sophisticated technology would breathe new life into a case grown cold with the passage of time and implicate her killer.