On Feb. 15, 1974, Mary K. Schlais was found dead in an intersection in the Township of Spring Brook, Dunn County, according to the sheriff's office there. Police said it was a homicide.
Schlais was from Minneapolis and police believe she was hitchhiking to Chicago for an art show.
Decades went by as investigators tracked leads, conducted interviews and examined evidence. The Dunn County Sheriff's Office said it used genetic evidence to find and arrest Jon Miller from Owatonna.
Authorities charged Miller with first-degree murder on Thursday, according to court records. He is in custody, awaiting extradition to Wisconsin.
How authorities identified Miller as a suspect
Charges filed Thursday say investigators found a stocking cap near Schlais' body in 1974 and collected hairs from it.
Years later, researchers used those hairs to develop a DNA profile of the suspect. Dunn County joined forces with Ramapo College in New Jersey, which specializes in genetic geneology. After interviewing and collecting DNA from multiple potential relatives, authorities were led to Miller, the criminal complaint states.
Before speaking to Miller, authorities went to his daughter and received her genetic profile. Research indicated the hair from the stocking cap belonged to her biological father. Investigators say the fact that Miller was adopted initially made it harder to track him down.
On Thursday, investigators met with Miller, who initially denied knowing about Schlais' killing. When told of the DNA evidence, Miller admitted to picking up Schlais while she was hitchhiking and asking for "sexual contact," the complaint states.
He allegedly told investigators that when she said no, he grabbed a knife he had stowed in the car and fatally stabbed her in the back.
Schlais had multiple stab wounds when she was found dead, according to the complaint, including defensive wounds on her hands.
According to the complaint, Miller said he pulled off the highway and tried to hide Schlais' body in a snowbank, but got scared when a car drove by and left the area.
Miller also admitted the stocking cap found at the scene was his, the complaint said. He was arrested following the interview with investigators and is being held at the Steele County Jail.
"We were sitting at the kitchen table last night and we got a call," said Mary Dodge, who lives with her husband Jack near the wooded spot where investigators discovered Schlais' body. Their neighbor Denny Anderson was driving by Miller as he was allegedly leaving Schlais' body in the snow, and he alerted authorities.
"Denny said when he went by the guy was just staring at him. He said he'll never forget the look on his face," Mary Dodge said.
Previous suspect was accused serial killer, former Green Bay Packer
In 2009, Schlais' body was exhumed and DNA testing allowed investigators to identify a suspect two years later: Randall Woodfield, a one-time Green Bay Packers draft pick who would later become known as the I-5 killer.
Authorities linked Woodfield to dozens of killings along Interstate 5 from Washington to California in the 1980s. He is in prison in connection to one murder, but has never confessed to any of the killings.
Woodfield was traveling from Portland to Green Bay at the time of Schlais' killing, authorities determined, and he matched a witness's suspect description. Woodfield was never further connected to or charged with Schlais' slaying.
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