A legal amendment allows DNA of executed killers to be added to the FBI database . An FBI detective hopes DNA will reveal additional John Wayne Gacy victims . He was convicted in 1994 of killing young men and boys in the Chicago area . He was executed in 1994 , before the national FBI database was created .
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 was executed in 1994 , before the national DNA database was created .