Hat from crime scene helps police crack decades-old cold-case murder of young hitchhiker

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The man who is suspected of murdering a young hitchhiker half a century ago has been arrested, thanks to DNA testing.

The arrest of Jon K. Miller, 84, was announced by the Dunn County Sheriff’s Office on Thursday. Miller, a resident of Owatonna, Minnesota, was charged with first-degree murder in connection to the 1974 homicide of Mary K. Schlais.

Investigators had been working on the cold case for 50 years. Schlais, a 25-year-old artist traveling from Minneapolis, was en route to an art show in Chicago when she was killed.

“Schlais was found deceased near the intersection of 408th Ave. and 990th St. in the Township of Spring Brook, Dunn County,” the Dunn County Sheriff’s Office said in a statement. “There was an eyewitness that observed a suspect and suspect’s vehicle that were believed to be connected to the homicide of Mary Schlais.”

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Mary Schlais, 25, was found dead near an intersection in Wisconsin in 1974. (Dunn County Sheriff’s Office/Google Maps)

Over the past 50 years, investigators have explored countless leads that have fallen short. It wasn’t until authorities worked with the Investigative Genetic Genealogy Center at Ramapo College in New Jersey that the case was able to progress.

Sheriff Kevin Bygd told Fox News Digital that a hat found at the crime scene led authorities to the suspect. During a press conference on Friday, Bygd announced that Miller had confessed to his involvement in the murder.

“When confronted with the evidence, 84-year-old Jon K. Miller confirmed his involvement with Mary’s homicide in 1974,” the official said.

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Jon K. Miller, 84, confessed to being involved in the 1974 murder. (Steele County Sheriff’s Office)

“I believe it’s got to even be a relief for him after 50 years of living with this,” Bygd said later during the presser. “[This has] had to have been on his mind almost every day. You would think [for] anybody with a conscience, it would.”

The sheriff also noted that hitchhiking was a common practice in 1974.

“You know, in 1974, it wasn’t that unusual for somebody to hitchhike from Minneapolis to Chicago,” Bygd said. “But stories like this is the reason we don’t let our kids do it anymore.”

Mary Schlais was hitchhiking to an art show in Chicago when she was killed. (Dunn County Sheriff’s Office)

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“This was a very bright young lady who had a very bright future ahead of her,” he added. “And her life was taken away from her way too soon.”

Andrea Margolis is a writer for Fox News Digital and Fox Business. Readers can send story tips to andrea.margolis@fox.com.