Genetic Genealogy Helped Crack The Brutal Murder Of 18-Year-Old Angie Dodge


More than two decades after 18-year-old Angie Dodge was raped and fatally stabbed in her apartment in Idaho Falls, the new forensic science of genetic genealogy has finally helped find a suspect whose DNA matches semen left at the scene.

At a Thursday press conference, the Idaho Falls Police Department announced the arrest of Brian Leigh Dripps Sr., 53, from Caldwell, Idaho. At the time of the murder, he lived on the same street as Dodge.

“His DNA matches the DNA sample left at the scene of the crime,” police chief Bryce Johnson said. “And he has also confessed to the crime in an interview.”

The case highlights how far the science of sleuthing in genealogy databases has come in the last five years. In 2014, detectives working the case obtained a warrant that forced the leading genealogy company Ancestry to reveal the identity of a man who had put a DNA profile for his Y chromosome in a database that the company had recently acquired. The profile had a strong overlap — but wasn’t a perfect match — to semen found at the crime scene.

That DNA profile belonged to the father of a New Orleans filmmaker, Michael Usry. Detectives found Usry had connections to Idaho and had made a movie titled Murderabilia about the trade in artifacts linked to notorious killers. On that evidence, police got a warrant to detain Usry and take a sample of his DNA.

But it was a false lead. Conventional forensic DNA testing showed that Usry was not the killer. “Nobody ever thinks that they’re gonna get picked up by the police and taken into an interrogation room and questioned about a murder,” Usry told CBS News’ 48 Hours. “When it happens to you, it’s definitely a game changer.”

The Dodge investigation had a troubled history even before that misstep. In 1997, detectives suspected a local man, Ben Hobbs, who had been arrested for rape in Nevada. They pulled in a friend of Hobbs, 20-year-old Christopher Tapp, who confessed under interrogation to helping hold Dodge down while Hobbs and another man he didn’t know attacked her.

Tapp thought he would be given immunity for helping the police. But when a DNA test cleared Hobbs, Tapp was charged with aiding the rape and murder. Despite there being no physical evidence to tie him to the scene, Tapp was convicted. At his trial, he said his confession had been coerced.

Tapp was eventually released in 2017 after the Idaho Innocence Project won a review of the DNA and other evidence. But only the rape conviction was formally overturned. “They still called him a murderer,” Greg Hampikian, a biologist at Boise State University and founder of the Idaho Innocence Project, told BuzzFeed News. “You can imagine how easy it is to find a job or rent a house.”

The new breakthrough in the case came through testing the crime scene sample for hundreds of thousands of genetic markers across the entire genome, rather than the few dozen on the Y chromosome that falsely implicated Usry.

Parabon NanoLabs, a DNA analysis company in Virginia that has worked with police on dozens of other cases over the past year, then uploaded that profile to a website called GEDmatch, used by people researching their family trees to look for possible relatives.

Parabon’s lead genealogist, CeCe Moore, drew up three family trees from partial DNA matches at GEDmatch, which converged on a single couple that seemed to be the perpetrator’s great-grandparents.

This couple’s descendants led to a handful of suspects, whom detectives shadowed to pick up items carrying DNA they had discarded. But when those samples were tested, none of the men were the perpetrator. “We originally had it narrowed down to about six men, but it turned out there was a seventh,” Moore said.

Eventually, Moore realized that one woman in the family had conceived a son shortly before she divorced. That child was Dripps, who took the name of the woman’s new husband.

Detectives tailed Dripps and picked up a cigarette butt thrown from his vehicle. When it was tested for DNA, it matched the semen from the crime scene.

The arrest brings some closure to the Dodge family. “I can’t even express how hard this journey has been,” a tearful Carol Dodge, Angie’s mother, said at the press conference.

“This is a great day for our family,” Brent Dodge, Angie’s brother, said. “We’re safe tonight. The bad guy is behind bars.”

Johnson, the Idaho Falls police chief, declined to comment when asked whether Tapp would now receive an apology and reparations for his long imprisonment. “That would be a question for a couple of weeks from now,” he said. “We need a little bit more time to dot ‘i’s and cross ‘t’s.”

“I hope they will do the right thing and admit that they made a mistake,” Tapp told BuzzFeed News. “I believe and hope to god that they will.”



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