– Matthew Klaus struggled with alcohol and heroin addiction, but his family thought things were improving this year.

He rented a house of his own for the first time and was eager to plant a garden. He had a new job. Even though he was in the throes of a relapse, he had recently completed 14 months of sobriety — his longest stretch without chemical abuse since he was a child.

Then, in March, their greatest fear came true: Klaus, 32, died of an overdose. What they learned a few days later through news accounts compounded their grief — he was a confidential informant with Rochester police who participated in drug buys.

"I'm hoping an addict is not expendable for the benefit of the community," said his father, John Klaus. "I struggle with what to believe there. I'd like to believe — I hope the police department considers both the needs of the addict and how they're using the addict when they try to do things for the community."

Klaus had a long history with Rochester police and nearly died of an overdose in 2017. The department paid him three times in March to buy purported heroin from Michelle A. Williams. She later allegedly sold Klaus his fatal dose.

While it is common for police to employ people with criminal records as informants, Klaus' death is reigniting the debate about the highly confidential practice.

Klaus' father and mother, Denise, said they were initially "confused and upset" upon learning of their son's work; but after speaking with police, they believe authorities acted reasonably and have no grievances against them.

In an interview supervised by Rochester City Attorney Jason Loos, Police Chief Jim Franklin said Klaus initiated the relationship with the department.

"We have refused to work with informants in the past based on their addictions," Franklin said. "In this particular case, there were no signs that he was intoxicated."

Franklin defended his department, even though working with Klaus violated its own policy by not seeking approval from his probation officer.

The department shows a grave misunderstanding or complete disregard for how addiction works, said Klaus' ex-girlfriend and close friend, Sarah Peterson.

"You're throwing it back in their face, basically, saying, 'Go pick up these drugs and don't use them,' " she said. "It's like you're fighting fire with fire."

Informant's first buy

Already on probation until 2023 in one case, Klaus was sentenced Feb. 20 to three years' probation for driving after his license had been canceled.

Less than a month later — on March 13 — Klaus made his first controlled buy from Williams under police guidance. He made buys on March 19 and 21, turning over the purported heroin to police each time. Police could not say how much Klaus was paid because of the cases against Williams. However, records show that Rochester police paid Klaus $100 for a "controlled buy" two times in January 2016 and $150 later that month for a "buy/bust."

Informants can play an important role in infiltrating criminal circles through their connections, said law enforcement officials.

Departments set their own policies for informants, although agencies using state grants must adopt guidelines set by the state Violent Crime Coordinating Council.

"The bottom line is, we have to be very careful about who we use … because ultimately, at the end of the day, we're responsible for them," said Anoka County Sheriff's Lt. Brent Erickson, commander of the Anoka-Hennepin Narcotics and Violent Crimes Task Force, which is not involved in Klaus' case.

Dan Cain, a former heroin addict and president of the recovery program RS EDEN, said addicts have access that officers can't always duplicate.

"As a citizen, I want drug dealers off the streets," he said. "As a treatment professional, I want people alive and sober. It's a difficult balancing act."

Police in Minnesota aren't required to report the use of informants, the harm to them or the outcomes of their work to authorities. That's generally true across the country.

Alexandra Natapoff, a professor at the School of Law at University of California, Irvine, studies informants and runs the website snitching.org.

"There is almost no data on how often informants are killed, overdosed, injured or harmed by their work," Natapoff said. "Any story like this would … represent the tip of what is certainly a much larger iceberg."

Klaus had been sober at the end of 2017 and much of 2018. He relapsed in December.

According to court documents, Williams told police she used heroin and sold it to Klaus for more than two years. She allegedly admitted to selling tar heroin to Klaus at 11 a.m. on March 29. Police arrested her five days after Klaus was found dead on March 30. She is charged with third-degree murder and three counts of third-degree drug sales.

At the advice of city attorney Loos, Franklin ended a recent interview and declined to address why police didn't arrest Williams immediately after the controlled buys.

"It's a question that I had," said Denise Klaus. "Why did it take him dying … "

"To arrest her?" John Klaus said, finishing her sentence.

Rochester police's policy requires approval and "agreed upon protocols" from county corrections to work with people on probation.

"We follow the policy," Franklin said. "We do care for the welfare of our informants."

Travis Gransee, director of community corrections for Dodge, Fillmore and Olmsted counties, said he first learned of Klaus' work with police when a reporter told him in mid-July. Gransee's office had not approved Klaus' work.

"We are supposed to, on an individual basis, offer input in regards to those exact scenarios," Gransee said.

Gransee and Rochester police work two floors apart in the same building.

'What if ...'

The disconnect was news to Klaus' parents, who repeatedly called probation early this year to report their son's alcohol and heroin use.

"I don't have any anger toward the police department," John Klaus said. "I know they have a tough job. I do play the what-if games. What if they had taken my calls seriously?"

Cain, the recovery expert, said police are largely focused on building cases.

"They put [Klaus] in a situation where it was likely he would use, and they actually gave him money that any right-thinking person knows he is going to use to foster his own habit," Cain said. "But again, the societal benefit in their mind outweighed the need to protect this individual."

Asked if Klaus' history and 2017 overdose were concerning, Franklin said: "Those are two years old … next question."

On March 29, Matthew Klaus was excited to spend the weekend with his son and father at his parents' home in Oronoco making a wooden night light for the boy. But he didn't answer the door when they arrived to pick him up. John Klaus waited for 20 minutes before leaving.

He returned the next day. Through a back window he saw his son slumped over on a couch. Klaus was pronounced dead at the scene.

Asked whether the benefits of informant work outweighed the risks in her son's case, Denise Klaus struggled. Matthew was the third of her four children. He loved woodcarving, backpacking the Superior Hiking Trail, and, she said, "was just always happy, really easy going, smart."

"No, not in our case," she said. "I mean, we lost Matthew … but we could've lost him even without him having been a — I don't know. I don't know."