Officials detail how DNA helped find alleged killer in Mary Schlais case

MENOMONIE, Wis. — An 84-year-old Owatonna man was arrested last week for a murder that took place 50 years ago in western Wisconsin.
On Monday afternoon, Dunn County investigators and a New Jersey genealogy lab discussed what it took to track down Jon K. Miller, and get justice for Mary Schlais.
“Although this case is very old, at this agency, it has never collected dust,” said Dunn County investigator Dan Westlund.
The investigation into the murder of the University of Minnesota graduate student began in February 1974, when her body was discovered in rural Spring Brook Township. She was last seen hitchhiking to an art show in Chicago.
An autopsy revealed she had been stabbed several times.  
“I think I speak for everyone involved when I say thank you for not giving up on this case,” said Dunn County Sgt. Jason Stalker.
A stocking cap found at the murder scene helped law enforcement build a suspect profile. That was all they had for decades, until things took a sudden turn.  
Investigators said genetic genealogy helped solve the case, and a lot of credit goes to the IGG Center at New Jersey’s Ramapo College.
“It’s a lead that we turn over to law enforcement like someone calling into a tip line,” said IGG director David Gurney.
Gurney and Carenn Binder connected with Dunn County in 2023. IGG used DNA from the stocking cap — along with ancestry sites like Family Tree DNA and GED Match Pro — to give detectives names of the suspect’s relatives. That took them from Wyoming to Michigan, and finally to Miller in Minnesota.  
“The family tree research in this case was very complicated and it took over a year for our investigative genetic genealogy research to bear fruit,” Binder said.
The fact that Miller was adopted made this case far more challenging. But in front of Schlais’ family, Dunn County authorities were finally able to announce that justice is close. Detectives said when Miller was confronted with the evidence, he confessed to the crime.
“Upon conclusion of interviewing Jon Miller, he did inform us that as soon as he had opened the door, he knew why we were there,” Westlund said.
Miller has been extradited from Owatonna to the Dunn County Jail.
Schlais’s family tells WCCO they plan on holding their own press conference in the future, but they wanted to thank law enforcement for the IGG Center for all their work.