By Bria Brown

DETROIT (AP) — The Michigan appeals court threw out conspiracy, theft and drug convictions and a six-year prison sentence after finding “true misconduct” by a prosecutor in a small county.

The court was amazed that Scott Koerner didn’t disclose that he had represented a co-defendant in the same crime before becoming an assistant prosecutor in Shiawassee County. He’s now the elected prosecutor.

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“This is such a highly disturbing set of facts,” Judge Amy Ronayne Krause said while hearing arguments on Jan. 8.

Aaron Mienkwic was accused of driving Kyle Tower to retail stores to steal merchandise in 2017. He was convicted and sentenced to more than six years in prison.

Koerner was a lawyer in private practice when he represented Tower months earlier in a plea deal. When Mienkwic went to trial in 2018, Koerner was on the other side as an assistant prosecutor.

He even called Tower as a star witness against Mienkwic.

The appeals court last week threw out the convictions. Koerner’s “close relationship” with Tower was never disclosed to Mienkwic or his attorney and “was not even commented upon by the trial judge,” the court said in a 3-0 opinion.

It’s a “rare occurrence of the prosecutor’s actions rising to the level of true misconduct,” the court said.

An email seeking comment from Koerner wasn’t immediately returned Monday. In an affidavit, he told the appeals court that he believes he disclosed his previous work to Mienkwic’s trial lawyer but doesn’t “recall the date of the discussion.”

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“I would never do anything to jeopardize a trial,” Koerner told The Argus-Press newspaper.

Nonetheless, Michigan rules of professional conduct say a government lawyer can’t get involved in a case after having an earlier role while in private practice.

“And the reason this rule is in place is because those attorneys have private information that gives them an unfair advantage. And that’s what we have here,” said appeals court Judge Brock Swartzle.

Mienkwic has already served one-third of his minimum prison sentence but still could face a second trial by a different prosecutor. It will be up to the attorney general’s office to decide whether to ask the state Supreme Court to look at the decision.

The winning appeal was filed by attorney Katherine Marcuz with assistance from University of Michigan law students. They had discovered that Koerner earlier had been tied to the case as a defense lawyer.

“It was very surprising,” Marcuz said Monday. ”We thought it had to be a typo.”

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