Colorado detectives use online DNA databases to solve cold cases – Canon City Daily Record

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DNA

Growing up, Alyssa Perea never understood why her father got so upset when she watched crime shows on TV.

Then in August, an investigator from the Douglas County Sheriff’s Office flew to Seattle and asked Perea’s mother and sister for a DNA sample, and her father’s aversion to the shows started to make more sense — he was a suspect in a 1981 murder in Jefferson County.

Perea’s family immediately wanted to help investigators, Perea said, both for the sake of the victim’s family and for their own sake, to know the truth, seven years after their father’s death.

“Is this really another thing my dad did? That inner knowing wants to know too,” she said. “We can’t ask him today. There is peace for everybody to know. And for my own family to further connect the dots of why little things make sense that we are trying to heal from as well.”

Jeannie Marie Moore

Perea’s sister gave a sample, and it was a match. Their father, Donald Steven Perea, killed 18-year-old Jeannie Moore, the sheriff’s office announced in September.

The killing was likely the first case in Colorado solved through the use of online genealogical databases, but it wasn’t the last. This week, Douglas County authorities announced first-degree murder charges against 62-year-old James Curtis Clanton in the 1980 killing of Helene Pruszynski in Castle Pines.

Authorities found both men by testing DNA found at the crime scenes, then checking that DNA for matches against DNA from more than a million people in an online database. Matches reveal family members, and from those family members, researchers can work backward to create a genetic family tree that eventually points to a real-life suspect.

The technique exploded in popularity after authorities in California used it to identify the Golden State Killer in 2017 and continues to offer promising new leads, particularly in cold cases.

It’s a process that relies on family members donating their DNA, something they often do without hesitation, said CeCe Moore, a genetic genealogist at Parabon Nanolabs, a Virginia company that worked on the Pruszynski case and has identified 90 suspects in violent crimes through genetic genealogy.

Helene Pruszynski

“In a sense, none of us want to implicate a family member,” she said. “But in another sense, these are highly violent crimes, and often sexual. Most people want to ferret out someone like that in their family anyway. If they are victimizing strangers, they may well victimize their own families.”

Perea, 27, who lives in San Diego but grew up in Pueblo, said her father was emotionally, sexually, verbally and physically abusive before he died in 2012. Learning the full extent of his past crimes helped put her own experience with him into perspective. The woman her father killed was last seen hitchhiking on Aug. 25, 1981. Her body was found five days later; she had been bludgeoned to death.

“Aside from having sympathy for the (victim’s) family, for myself it’s almost empowering to understand the weight of everything that I’ve been through,” she said. “I’m very proud of the person I am today despite the things I faced. For me, that confirmation is a lot of things. It’s ‘Do I still love my father? Did he love me?’ It raises a lot of those questions.”

For Jessi Still, whose DNA helped authorities identify Clanton this year, the experience was much less personal. She’d had her DNA tested to learn about her ancestry and ethnicity, she said, and after the Golden State Killer was arrested in 2017, she decided to upload her DNA  profile to an online, public database called GEDmatch so it could be used for research.

“Honestly, I thought it was cool because GEDMatch is not just for law enforcement. It’s research projects, people looking for adopted family members, and looking for Jane and John Does,” she said. “It was just some way that was easy for me to maybe help someone. That was the motivation behind it.”

Still, who lives in Georgia, never expected to get a call from detectives in Colorado, a state she has no known connections to. The detective told her that she was a distant relative to a suspect in a 1980 case and asked if she would share her genealogical research and ancestry information.

Still thought it might be a prank, but after checking to be sure the sheriff’s office and the detective were legitimate, she didn’t hesitate.

“I was thinking about her family and them finally having some answers,” she said.

More answers might be forthcoming for more families, said Mitch Morrissey, retired Denver district attorney and the co-founder of United Data Connect, a local company that helped authorities identify Clanton and Perea.

The company has identified persons of interest in two other cases that date to the 1960s, Morrissey said Wednesday, although the details of the cases have not yet been made public.

Once a potential suspect has been identified through genealogy, it’s up to law enforcement to build the case, track down other evidence and confirm that person as the suspect.

“We’ve got two more where we are done with our work and the work is being done by the detectives,” Morrissey said.

He added that the technique is far from a silver bullet. It can be used only when there is a large sample of DNA from a single person; often DNA samples are too small or contaminated for the testing to be effective.

Additionally, the key DNA database law enforcement has used — GEDMatch — changed its policies in May to require users to opt in and give explicit consent in order for their DNA to be used by law enforcement. Overnight, the DNA available to law enforcement dropped from more than 1 million profiles to zero.

That has since ticked up steadily as donors have opted in, and today law enforcement can access about 200,000 DNA profiles, Moore said, adding that she’s not sure the Clanton case could be solved today, given the reduced database.

Many people who uploaded their DNA to the site have since died, she said, making it impossible for them to give consent.

“Genealogists tend to be retired and older, and the database has been around for a while, so it’s like burning libraries,” she said. But, she added, it is important for people to know how their information is being used.

And despite the limitations, the technique nevertheless remains a powerful tool, Morrissey said.

“You can change your name, you can use aliases, but in terms of DNA, it doesn’t matter what you call yourself,” he said. “The DNA isn’t going to change.”