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Monday, December 3, 2012 Sheriff Tom Dart's efforts to bring closure to all facets of the John Wayne Gacy serial murder investigation, the Cook County Sheriff's Police have obtained a DNA profile for Gacy and added it into CODIS (Combined DNA Index System). It is believed that such a submission has never been done before in the United States for executed offenders predating the DNA database.

CODIS is a Federal Bureau of Investigations (FBI) DNA database containing various types of profiles organized into indexes that include those of convicted felony offenders, homicide victims, and missing persons. Cook County Sheriff's Police Cold Case Unit wanted to add Gacy's DNA profile into the system to be compared against all unknown DNA profiles found at major crime scenes around the country. This would be an innovative attempt to possibly identify additional unknown Gacy victims. In order to have a profile entered into CODIS under the convicted felony offender index, the offender would have had to have been in prison since the inception of the CODIS law in the early 2000s. Gacy did not fall under the law because he was executed for his crimes in May of 1994.

After researching the CODIS indexes, the Sheriff's Cold Case Unit found a CODIS index that includes the language, "death by homicidal means," which contains DNA profiles by homicide. Based on that language the Unit was then able to present that technically, John Wayne Gacy's death was a homicide by lethal injection. After review, the Illinois State Police Crime Lab deemed this interpretation acceptable and Gacy's DNA profile was to be obtained and entered in CODIS.

Will County Coroner Patrick O'Neil has preserved Gacy's blood sample from his execution at the Illinois Department of Corrections Stateville Penitentiary in Will County. O'Neil has submitted the sample to the Illinois State Police Criminal Laboratory at the Cook County Sheriff's Office request to obtain a DNA profile which will be entered into CODIS. Coroner O'Neil has agreed to submit several other executed offender profiles through the same manner.

This new interpretation will assist the Cook County Sheriff's Police Department Detectives, as well as other law enforcement agencies, in discovering if Gacy committed any other murders in other parts of the country. It will also set a precedent for other law enforcement, coroner and medical examiner agencies to submit biological samples of executed offenders to be included in CODIS and to help close cold cases.

"This has the potential to help bring closure to victims' families who have gone so long without knowing what happened to their loved ones," Sheriff Dart said. "We are proud to have helped pave an additional avenue to do that."

The Cook County Sheriff's Office would like to thank the Illinois State Police and Will County Coroner Patrick O'Neil for their assistance in creating this new route that has the potential to aid in the investigation of unsolved cases.

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