No criminal charges will be filed against a former Eden Prairie police detective whose false statements led to the dismissal of murder charges against an admitted drug dealer.

McLeod County Attorney Michael Junge, in a release issued Friday, called the result of his investigation distasteful because the former detective, Travis Serafin, “falsified an application for a search warrant and does not face criminal punishment. An officer intentionally gave false testimony and cannot be charged.”

To charge Serafin with a crime, Junge said in the release, prosecutors would have to show that they had obtained information about his activities from a source other than his own statement.

The state would have been unable to prove that no part of its case went untainted by Serafin’s compelled statement, Junge said.

In November, the Hennepin County Attorney’s Office announced problems with Serafin’s search warrant in a heroin case that led to drug and murder charges against Timothy Holmes.

Because Serafin was found to have lied, the prosecutor dismissed charges against Holmes, dropped pending charges against others and opened investigations into former cases handled by the detective.

At the time, prosecutors said 32 cases were targets for dismissal because Serafin was a critical witness, but the result ended up much higher.

On Friday, the Hennepin County attorney’s spokesman said prosecutors had sent letters asking that guilty verdicts be thrown out and that in 24 other cases, prosecutors dismissed charges against defendants before trial. In additional cases, the county attorney notified defense attorneys that Serafin had been a peripheral witness on their case.

The question of whether criminal charges should be filed against Serafin was referred to Junge because of a conflict of interest with Hennepin County, where prosecutors had worked with the detective.

The inability to file criminal charges is tied to the investigation conducted by Eden Prairie police into Serafin’s activities.

When the potential problems surfaced, Serafin became the focus of an internal police disciplinary action. As a condition of his employment, Serafin was compelled to give a sworn statement to the department about what he had done. But in criminal matters, defendants cannot be compelled to provide testimony against themselves.

The problems became public last October, when Hennepin County officials said that while Serafin had a search warrant for Holmes’ house, where drugs were found, he didn’t have a warrant to search his car where additional drugs and a gun were uncovered.

A week after making the search, Serafin created a second warrant application that covered both the house and car. When asked under oath in court about the two applications, Serafin blamed clerical confusion during a hectic time at work.

As a result of Serafin’s search, Holmes was charged with first-degree drug sale and third-degree murder related to the overdose death of a person to whom Holmes was alleged to have sold heroin.

In March 2018, Holmes pleaded guilty to the first-degree drug sale charge. As part of the plea, Hennepin County Judge Fred Karasov dropped the third-degree murder charge in the death of Margaret “Maggie” Lane.

Holmes was sentenced to six years in prison, but he has since been released.

In his findings, Junge said that Serafin committed neither forgery nor perjury.

No legal rights were violated with the warrant application, Junge wrote. While the alteration of the search warrant application wasn’t forgery, the alteration of the search warrant would have been, Junge said.

And Serafin didn’t commit perjury even though he lied in court under oath, Junge said. His false statement wasn’t “material” because it had no effect on the search warrant and its execution.

“The untruthful testimony certainly negatively impacts the credibility of Officer Serafin in this and all other matters he has worked on,” Junge wrote.

Serafin’s last day with the Eden Prairie department was Nov. 6. He had worked for the department since October 2000 and earned $92,289. He was once named the department’s officer of the year. He was also a member of the Southwest Hennepin Drug Task Force, whose work was suspended after the trouble with Serafin.

Serafin hasn’t publicly commented. His attorney did not respond to a request for comment Friday.