(CNN) Before he became Jeff Sessions' chief of staff, Matthew Whitaker worked as the executive director of the Foundation for Accountability and Civic Trust, a Washington nonprofit funded almost entirely by dark money.

On its website , the group proclaims it is "dedicated to promoting accountability, ethics, and transparency in government and civic arenas." But the accountability it has sought is almost exclusively related to Democrats.

Since its founding, FACT has filed complaints and called for investigations into dozens of Democrats, and in the group's early days, Whitaker focused his efforts on Hillary Clinton.

In February 2015, FACT filed a complaint accusation with the Federal Election Commission that a Democratic data firm was running an "illegal coordination scheme" with party campaigns and labor unions. That data firm, Catalist, was run by Harold Ickes, a longtime Democratic strategist and President Bill Clinton's former deputy chief of staff.

Amy Weiss, a spokeswoman for Catalist, said the complaint "was deemed to be without merit."

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