Washington County Attorney Pete Orput will not seek re-election for a fourth term and plans to retire at the end of this year, he said Friday.

The announcement comes more than year after Orput, 66, publicly revealed that he had been diagnosed with Parkinson's disease. He was first elected Washington County attorney in 2010.

"It's sometimes thankless, but I think it's just been the greatest opportunity of my life," he said Friday. He credited his staff for their work ethic, saying the attorneys in his office are effective because "they give a damn."

In a statement released Friday by his office, Orput said he was "incredibly proud" of the work his staff has done to advance justice.

"We've markedly improved the operations of the county attorney's office. We've established a veterans court. We've addressed the scourge of opioid addictions. And we've locked up sex traffickers and murderers," he said in the statement. "Most importantly, we've helped victims of crime."

A former Marine who served in Vietnam, Orput was a high school history teacher before entering the law. He worked for the Minnesota Attorney General's Office, served as general counsel for the state Department of Corrections, and prosecuted violent crime for the Hennepin County Attorney's Office.

In Washington County, Orput gained a reputation for pursuing steep criminal charges against heroin dealers, charging them with third-degree murder in overdose deaths. He also worked hard to get treatment for addicts who had fallen into the criminal justice system.

"I think we're very compassionate with those who have become addicted," he said, "but we're less so with those who are feeding what's still going on."

Orput helped lead an effort in 2017 by county attorneys to sue the manufacturers and distributors of opium-based painkillers. The suit — which settled last year for more than $300 million — sought money to cover state, county and city costs in fighting the opioid epidemic.

He helped create the veterans courts in Hennepin and Washington counties. And Orput targeted human trafficking, saying it's far more common in Minnesota than most people realize. He was instrumental in the creation of the Minnesota Human Trafficking Task Force.

"The only thing you can do is change the equation, make the risk really high," he said.

Orput was the special prosecutor in the case of Byron Smith, the Little Falls man convicted in 2014 of fatally shooting two unarmed teens who had broken into his home on Thanksgiving Day 2012.

Last year, Orput was targeted by activists who wanted him to upgrade the criminal charges against former Brooklyn Center police officer Kimberly Potter for the shooting death of Daunte Wright. Orput was originally assigned the Hennepin County case under a system enacted by metro-area county attorneys that sought to eliminate the appearance of bias in the prosecution of police shootings.

He eventually returned the case, and a key staffer in his office resigned, citing the vitriol surrounding Potter's prosecution. Potter was convicted last month on charges of first- and second-degree manslaughter.

The stress of the job has become more of a concern now that he's fighting Parkinson's, Orput said. The COVID-19 pandemic also added significantly to the backlog of cases his office is handling, which triggered more stress.

"You know when you need to leave," he said Friday.

Orput said he plans to spend some of his retirement volunteering but has no formal plans beyond stepping down on Dec. 31.