We previously have featured the story of Michael Lutz, the Wisconsin whistleblower and former prosecutor who alleged that the union-operative wife of “John Doe” prosecutor John Chislhom was behind the targeting of conservative activists that recently was thrown out by the Wisconsin Supreme Court.

Was Prosecutor’s union-operative wife behind “John Doe” investigation of Scott Walker? (quote via Stuart Taylor):

Now a longtime Chisholm subordinate reveals for the first time in this article that the district attorney may have had personal motivations for his investigation. Chisholm told him and others that Chisholm’s wife, Colleen, a teacher’s union shop steward at St. Francis high school, a public school near Milwaukee, had been repeatedly moved to tears by Walker’s anti-union policies in 2011, according to the former staff prosecutor in Chisholm’s office. Chisholm said in the presence of the former prosecutor that his wife “frequently cried when discussing the topic of the union disbanding and the effect it would have on the people involved … She took it personally.”

Citing fear of retaliation, the former prosecutor declined to be identified and has not previously talked to reporters.

Chisholm added, according to that prosecutor, that “he felt that it was his personal duty to stop Walker from treating people like this.”

Lutz stuck to his story even after furious pushback, as reflected in this interview with Charlie Sykes:

Lutz also appeared on Fox News to tell his story:

Now Lutz is dead, of what police are terming an apparent suicide (via Instapundit via Althouse). The Milwaukee Journal Sentinal, a harsh critic of Lutz, reports:

Former aldermanic candidate Michael Lutz died early Sunday morning of an apparent suicide, according to the Milwaukee County Medical Examiner’s Office.

Lutz, 44, a former Milwaukee police officer, suffered an apparent self-inflicted gunshot wound “while in the presence of Menomonee Falls tactical officers after a brief tactical situation,” the medical examiner’s office said in a release issued Sunday.

Lutz was pronounced dead in the 12300 block of W. Mill Road in Milwaukee at 4:05 a.m., the release said. An autopsy is scheduled for Monday.

Menomonee Falls police are investigating the incident.

Lutz finished fourth in Tuesday’s primary in the 11th Aldermanic District to fill the Common Council seat left vacant by the death of Joe Dudzik. He received 426 votes out of 4,155 ballots cast.

He retired from the Milwaukee Police Department after 17 years, initially receiving taxpayer-funded duty disability pay for post-traumatic stress disorder. His pay was later converted to a regular retirement.

In 2005, Lutz was shot in the arm after he and his partner chased a suspected drug dealer into a house on the city’s near south side. He never returned to active duty.

Lutz later became a criminal defense attorney and was the anonymous source for a series of stories last year critical of Milwaukee County District Attorney John Chisholm.

The circumstances are not clear at this moment, as there apparently was a police tactical unit on the scene:

The Medical Examiner’s Office says Lutz died as a result of one apparent self-inflicted gunshot wound while in the presence of Menomonee Falls tactical officers — after a brief tactical situation.

We will update as more details become known.

UPDATE 8:50 p.m. Eastern: M.D. Kittle of Wisconsin Watchdog, who was the authority on the John Doe cases, has more details, A tragic end for a John Doe whistleblower:

Menomonee Falls Assistant Police Chief Mark Waters said his department’s tactical unit responded to reports of a suicidal man in the 12300 block of W. Mill Road in Milwaukee County. The incident had begun in Menomonee Falls.

“We tried everything we could do to prevent it, but he eventually committed suicide in our presence,” Waters told Wisconsin Watchdog.

Lutz was pronounced dead at 4:05 a.m. Sunday.

The Milwaukee County Medical Examiner’s Office was expected to release an autopsy report Monday.

Waters said the police department would not make additional comments or issue a press release on a suicide.

Sources close to the situation told Wisconsin Watchdog that Lutz argued earlier in the day with his ex-wife, Lori, who resides in Menomonee Falls, and had threatened to hurt her boyfriend.

Police had Lutz’s vehicle information and stopped him, sources said. One of the officers responding thought he heard the racking of a firearm as he approached Lutz’s vehicle. They backed off and called in the tactical team.

Sources said Lutz never threatened officers but did not comply with orders. He eventually got out of the vehicle, placed a Glock handgun in his mouth and pulled the trigger.