Former Trump campaign chairman Paul Manafort has sued special counsel Robert Mueller, Deputy Attorney General Rod Rosenstein and the Department of Justice in U.S. federal court, alleging that Mueller has strayed beyond the scope of the investigation he was authorized to pursue.

Manafort's suit also alleges the order appointing Mueller exceeds the deputy attorney general's authority. As a result, all actions taken by the special counsel "must be set aside," it argues.



"The actions of DOJ and Mr. Rosenstein in issuing the Appointment Order, and Mr. Mueller's actions pursuant to the authority the Order granted him, were arbitrary, capricious, and not in accordance with the law," the suit reads.

The appointment order authorizing Mueller as special counsel permits him to investigate any matters that "may arise directly from the investigation." Experts have said it gives Mueller wide latitude to determine the course of his investigation.

"I think it's going to be an uphill battle," said Sol Wisenberg, a leading white-collar attorney, referring to Manafort's suit. "These kinds of things usually don't prevail."

Manafort was indicted Oct. 27 on 12 counts related to unlawful financial dealings. He pleaded not guilty and has been contesting the charges. A trial is scheduled to begin in May.

The special counsel's office declined to comment.