The targets of a politically charged investigation in Wisconsin are now targeting the state's Government Accountability Board, alleging in a lawsuit the agency that oversees election and campaign finance law has created a "Frankenstein monster" out of its enforcement authority.

The GAB has "exceeded its statutory authority and evaded its statutory obligations by pursuing and funding a far-reaching criminal investigation into virtually every conservative-leaning group in Wisconsin," according to the lawsuit, filed Friday morning in Waukesha County Circuit Court by conservative activist Eric O'Keefe and his Wisconsin Club for Growth, and on "behalf of others similarly situated."

O'Keefe takes particular aim at the GAB and its involvement in the John Doe probe, a nearly three-year investigation into 29 conservative issue advocacy organizations.

The court-administered dragnet, launched in late summer 2012 by Milwaukee County District Attorney John Chisholm, a Democrat, is nothing more than a partisan witch hunt, O'Keefe asserts in a civil rights lawsuit filed earlier this year in federal court against John Doe prosecutors.

In that complaint, O'Keefe argues that the prosecutors violated his First Amendment rights via an investigation that, sources say, involved pre-dawn, "paramilitary-style" raids on the homes of conservative targets.

And it was all done with the backing of the Government Accountability Board, using powers not ascribed to the board, O'Keefe's lawsuit alleges.

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