A legal loophole allows DNA of executed killers to be added to the FBI database . An Illinois detective hopes DNA will reveal additional John Wayne Gacy victims . Gacy was convicted in 1980 of killing 33 men and boys in the Chicago area . His DNA was never added to the FBI 's national DNA database -- officially called the Combined DNA Index System or CODIS -- because it did n't exist when he was put to death in 1994 . He is serving life without parole for his crimes, which included dismembering bodies with a chainsaw before dumping them into trash cans around town.
A legal loophole allows DNA of executed killers to be added to the FBI database . An Illinois detective hopes DNA will reveal additional John Wayne Gacy victims . Gacy was convicted in 1980 of killing 33 men and boys in the Chicago area . He is serving life without parole for his crimes, which included dismembering bodies with a chainsaw before dumping them into trash cans around town.