10. John Joubert
In 1983, two murders of schoolboys rocked the Omaha, Nebraska area. The body of one of the boys was found tied with a type of rope that investigators couldn’t identify. While following up on the lead of a mysterious man scouting out a school, they traced the suspect’s license plate to John Joubert, a radar technician at the local Air Force base. In his belongings, they found a rope matching the unusual one used in the murder (which turned out to be Korean). Although DNA analysis technology was not yet an option, the extreme rarity of the rope was enough to lead to Joubert’s confession. Furthermore, hair from one of the victims was found in Joubert’s car. The child killer was even linked to a third murder, in Maine, when his teeth were found to match bite marks on a boy killed in 1982. Joubert was found guilty of all three murders and was put to death in the electric chair in 1996.