CINDY ARCHER: Why I’m Filing a Civil-Rights Lawsuit: Milwaukee County District Attorney John Chisholm and his agents ransacked my house and ruined my career.

After much soul-searching, I am filing a civil-rights lawsuit on Wednesday against Milwaukee County District Attorney John Chisholm. I fear his retaliation, given what I know of his methods, but the Chisholm campaign against me that began at dawn on Sept. 14, 2011, requires a legal response to discourage the prosecutor’s continued abuse of his office.

Some background: Mr. Chisholm launched his first round of investigations into the affairs of Scott Walker in May 2010, when he was serving as Milwaukee county executive and Mr. Walker’s office reported the disappearance of some charitable funds. Rather than seek out the perpetrator—whom Mr. Walker’s office had also identified—the district attorney’s crew turned its attention to Mr. Walker and his staff.

The investigation grew in size, scope and intensity as Mr. Walker rose in Wisconsin politics, eventually winning election as governor in 2011, reforming public-employee union laws and prevailing in recall elections. By that time, the investigation by Mr. Chisholm, a Democrat, had moved well beyond the matter of the missing funds, citing a grab bag of potential offenses as justification to vacuum up the internal communications of Mr. Walker’s aides, apparently for anything that could be used against the Republican governor.

I was a close adviser to Scott Walker in the county executive’s office and then in the statehouse, but it never occurred to me that my own happiness would be collateral damage in a political vendetta.

Nothing could have prepared me for waking up to the shouts of men with battering rams announcing that they were about to break down my door on that morning in 2011. It was so unexpected and frightening that I ran down from my bedroom without clothes on. Panicked by the threatened show of force, I was then humiliated as officers outside the window yelled at me to get dressed and open up. I quickly retrieved clothing and dressed as I unlocked the door.

Agents with weapons drawn swarmed through every part of the house. They barged into the bathroom where my partner was showering. I was told to shut up and sit down. The officers rummaged through drawers, cabinets and closets. Their aggressive assault on my home seemed more appropriate for a dangerous criminal, not a longtime public servant with no criminal history.

After they left, I surveyed the damage. Drawers and closets had been ransacked. My deceased mother’s belongings were strewn across the floor. Neighbors gathered in small clusters at the end of their driveways and the press arrived in force.

What had prompted the raid? My guess: As an adviser to Gov. Walker, I had played a lead role in drafting and implementing public-employee labor reforms that would propel him to the national stage.

This was a serious abuse of power for the most craven of political reasons. John Chisholm and his minions should end up broke, unemployable, and possibly in jail. As an example to the others.