Crime

MADISON, Wis. (AP) ― A University of Wisconsin-Madison dropout was charged Friday in the murder of a 31-year-old man, potentially solving one of several murders that had frightened city residents.

Adam C. Peterson's DNA matched a sample taken from a knife used to kill Joel Marino in his lakeshore home Jan. 28, according to a complaint charging him with first-degree intentional homicide.

Mayor Dave Cieslewicz said the charge was a relief to residents worried about their safety after three high-profile murders went unsolved for months. He praised detectives for good police work.

Police said they have not established a link between Peterson and the April death of UW-Madison student Brittany Zimmermann or last summer's murder of 22-year-old Kelly Nolan, who disappeared after a night of barhopping. Police Chief Noble Wray said the investigation continues.

"There is a great sense of relief in reaching some closure with this particular homicide investigation," Wray said at a news conference. But he added later: "There's still a lengthy road ahead for the Madison Police Department with this investigation and other unsolved homicides."

An intruder stabbed Marino twice in the abdomen and chest in his home in the middle of the day, police said. He was found dying in a nearby alley, after apparently trying to get to a hospital for help.

Police Capt. Jim Wheeler said detectives have not been able to establish any relationship between Marino and Peterson, 20, or a motive. Wray described the case as a stranger killing.

The murder of the popular environmentalist and musician who worked for a medical device company shocked the city. As months dragged on, police faced criticism for failing to catch his killer and fear swept the city after Zimmermann was killed.

Wheeler said detectives became interested in Peterson after the department had several interactions with him. Peterson reported his laptop stolen days before the murder and again a month later, saying he needed a police case number to get a replacement at a discount.

At some point after the murder, Peterson's roommates called police because they had concerns "and we had to check his welfare," Wheeler said. He declined to elaborate on that incident, which police spokesman Mike Hanson said was being reviewed.

Peterson was then included on a department bulletin as someone potentially having mental health problems, Wheeler said. He also looked similar to a police sketch developed after a witness saw someone running from Marino's house the day of the murder.

"Things just kept coming together," Wheeler said.

Peterson was arrested Thursday at his mother's home in Grant, Minn., where detectives served a search warrant seeking a DNA swab. A DNA test at the state crime lab on Thursday evening matched it with DNA taken from a paring knife with a 4-inch blade that was recovered from Marino's residence, the complaint said.

The DNA also matched samples taken from a Wisconsin stocking cap and a backpack that were recovered in a residential recycling bin, the complaint said.

Adam Peterson declined to challenge his extradition during a court hearing in Stillwater, Minn., on Friday afternoon and was expected to be transported to Madison. An initial court appearance has not been scheduled.

Peterson attended UW-La Crosse before transferring to UW-Madison last fall as a junior, UW-Madison spokesman John Lucas said. He said Peterson dropped his classes in October and officially withdrew from the university in November. He declined comment on whether the university noted any concerns about his behavior.

Peterson continued to live in Madison for several months and had several addresses, which detectives were still trying to trace, before he moved back to Minnesota, Wray said.

One address, according to the criminal complaint, was in an apartment complex about a block from the residence where Zimmermann was killed in April in a neighborhood populated with students. Marino's house was about one mile from there.

Peterson's father, Melvin Peterson, told the Wisconsin State Journal that his son returned home to Minnesota in March after a week-long stay in the psychiatric ward of a Madison hospital because he became so unstable that his brother called 911.

The elder Peterson told the newspaper Adam Peterson experienced a "psychotic episode" that "involved extreme verbal violence that his brother had not seen before."

Melvin Peterson said that since his return home, his son has been in intensive psychiatric care.

Steve Purdue, 41, said he was shocked to learn a suspected killer used to live next door but relieved Peterson was caught. Purdue said he started keeping a baseball bat by his door and wouldn't let his girlfriend walk in his neighborhood by herself after Zimmermann was killed.

"I was scared to death all the time," said Purdue, who moved to Madison from rural North Carolina. "I'm not used to stuff like that. I'm from the country."

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