Updated

A man who sued the prosecutors of a secret investigation into dozens of Wisconsin conservative groups now wants the lead prosecutor investigated on charges of using his office for political persecution and personal reward.

Long-time political activist Eric O'Keefe, a director of the Wisconsin Club for Growth, on Monday sent a certified letter to Milwaukee County District Attorney John Chisholm demanding that Chisholm ask the Milwaukee County Circuit Court to appoint a special prosecutor to investigate the conduct of the DA and his office.

Chisholm was not in his office Monday morning, according to an assistant. He could not be reached for comment.

O'Keefe notes that Wisconsin law prohibits a district attorney from using the powers and privileges of his office for the financial benefit of himself, his immediate family members, or an organization with which his immediate family members are associated.

A district attorney also is prohibited from using those powers and privileges to obtain an unlawful advantage for third parties, such as political candidates and recall committees; to obtain through official functions for those illegitimate purposes; and from allowing his office to become de facto campaign grounds.

"Recently, credible factual reports suggest that you may have done all these things," O'Keefe states in the letter.

He refers to recent bombshell allegations by former Milwaukee police officer Michael Lutz, who for several months served as an unpaid special prosecutor in Chisholm's office.

Lutz in an article earlier this month claimed that Chisholm, a Democrat, told Lutz in March 2011 of his personal vendetta against Republican Gov. Scott Walker.

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