Jeannie Moore was murdered in 1981, but her killer was only recently identified.Jefferson County Sheriff's Department

Jeannie Moore's killer was identified thanks to advancements in technology

The murder of Irish American teenager Jeannie Moore has been solved nearly four decades after the 18-year-old’s death in Colorado.

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On August 25, 1981, Moore was reported missing after she didn’t turn up for work. While her body was tragically discovered in a local park five days later, the search for her murderer ran cold.

NBC 9 News in Denver reports that investigators revisited Moore's case in 2008 and collected DNA from the crime scene.  In 2011, the samples were uploaded to the Combined DNA Index System (CODIS), but no matches were found.

In May 2019,  experts took another look at the DNA with the hope that new technology would help them find a familial match. CBS News reports that the DNA samples were shared with GEDmatch, an open-source website, and Family Tree DNA.

This time, there was a match: Donald Steven Perea. The results were confirmed after a cross-reference with Perea's relatives' DNA.

Genetic Genealogy 

Investigator Mitch Morrissey said Moore's case was cracked using “genetic genealogy,” an emerging forensics field.

“Anybody that has their ancestry results or their 23 and Me results that want to help law enforcement solve cases," Morrissey urges, "go to GEDmatch, upload your data and say ‘Yes’ to the question ‘Do you want law enforcement to have your data?'”

“It was Family Tree DNA that gave us the most significant lead in this case. For a few hundred dollars, law enforcement can upload their sample into Family Tree… and then you search for people with common DNA to the DNA that you’re looking for.”

“Then there’s a whole system where genealogist can look at it and say ‘OK, based on how much you share, this is likely a first cousin,’ or ‘This is likely an uncle’ or ‘This is likely, you know, some other relative.'"

“What this allows you to do is go out to about fourth cousins. On average, a person has about 850 cousins out there in the world.”

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On September 10, Colorado’s Jefferson County Sherriff Jeff Shrader announced that the testing proved Donald Steven Perea was responsible for the kidnapping, sexual assault, and murder of Jeannie Moore in 1981. 

Perea had been out on bond for sexual assault charges when he killed Moore. He served prison time from 1982 to 1985 and died of health issues in 2012.

The Jefferson County Sherriff’s Department said in a statement: “Further investigation led investigators to identify Perea as being 3.3 trillion times more likely than anyone else to have committed the murder.”

In the wake of the news, Moore's family, who have also requested privacy at this time, said they will remember Jeannie as “loving and kind in all her ways. She was sincere and true in her heart and mind, and has left behind beautiful memories.”

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You can watch the press conference from the Jefferson County Sherriff's Department here: