The only target of a Democrat-driven "John Doe" investigation to speak out publicly against what many Wisconsin conservatives see as a political witch hunt has made good on his promise to take prosecutors to court, charging they violated his civil rights.

Eric O'Keefe and his Wisconsin Club for Growth filed a federal civil rights lawsuit Monday against the special prosecutor, the presiding judge and top prosecutors in the Milwaukee County District Attorney's office.

"This secret investigation and gag order on conservative activists is intended to stop their political successes in Wisconsin," O'Keefe said in a news release. "The state cannot be allowed to silence political speech it does not like."

The lawsuit, led by Washington, D.C., attorney David B. Rivkin Jr., contends "Milwaukee County prosecutors are abusing their authority in retaliation for the Club's successful political activism in support of Wisconsin Republican Gov. Scott Walker's 'Budget Repair Bill,'" which reformed public-sector collective bargaining in the Badger State.

"Milwaukee County District Attorney John Chisholm and his staff have spent the past four years prying into the affairs of Scott Walker, his associates, and his supporters in a series of John Doe proceedings," the news release states.

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