A woman was killed in 1974 while hitchhiking to an art exhibition in Chicago. After 50 years, investigators found her killer

This week, investigators in Wisconsin used genetic genealogy to solve a 50-year-old case, charging an 84-year-old Minnesota man with the murder of a woman who was found dead in 1974.

According to the Dunn County Sheriff’s Office, 25-year-old Mary K. Schlice was found dead at an intersection in Spring Brook, Wisconsin on February 15, 1974. Her death was ruled a homicide, and the initial investigation indicated that she was hitchhiking to an art exhibit in Chicago when she was killed. the agency reports.

According to Dunn County Sheriff Kevin Bigd, John Miller of Owatonna, Minn., was arrested Thursday after he “confirmed his involvement” in Schleis’s murder. He is currently in custody in Steele County, Minnesota, awaiting extradition to Wisconsin, Bigd said.

“This is a huge win for our agency,” Bigd said at a news conference Friday. According to the sheriff, it is the first time the agency has used genetic genealogy to solve a case.

For decades, detectives from several law enforcement agencies assigned to the homicide case have received various tips and leads and conducted interviews, but no “viable” suspects have been identified, according to the sheriff’s office.

Evidence has also been examined and reviewed over the years, but it wasn’t until the agency began working with a team of genetic genealogists at Ramapo College in New Jersey in recent years that investigators were able to identify Miller as a suspect using genetic evidence, the department said.

Forensic genetic genealogy in accordance with US Department of Justice.

It combines forensic genetics, or DNA analysis, with traditional genealogy, or family history, to identify a person.

“Agencies can spend thousands and thousands of dollars sending DNA samples to private labs around the country to try to get results, and we had a college that was very willing to step up and help us in that process,” Sheriff Bigd said.

The two sheriff’s investigators who worked on the case, Dan Westland and Jason Stocker, said at a news conference that they had spoken with Schleiss’ family, who expressed relief and appreciation for the investigation.

The sheriff’s office did not elaborate on what DNA fragment investigators used to solve the case or the genetic genealogy process that led them to the suspect, saying they would leave that to Ramapo College officials at their briefing Monday.

The sheriff said investigators were thrown a “curve ball” in evaluating Miller’s family background because he was adopted.

“It’s going to take a lot more work that these guys have put in over the last couple of weeks to try to dodge that curve ball… We were able to sit down with him and have him confirm his involvement in her murder yesterday,” he continued.

Westland said that when he and Stoker spoke with Miller on Thursday, he was “pretty cool about what happened.”

“I think it must even be a relief for him after 50 years of living with it. It must have been on his mind almost every day. You would think that someone with a conscience would do that. So I think he’s done dealing with it personally,” Sheriff Bigd said.

Many of the detectives and former sheriffs who worked on the case over the years have passed away, said the sheriff, who added that he was “delighted” to tell some of his former colleagues who are still alive that the case has been solved.

“I was actually sitting on a deer stand when I got the message from the Westland investigator yesterday and I was having a hard time controlling my excitement,” Bigd said. “… I went through every investigator who picked it up and ran with it and hit a dead end.”

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