January 11, 1999
A federal employee assigned to a state or local government or other non-federal entity under the Intergovernmental Personnel Act is not prohibited by 18 U.S.C. § 205 from representing the interest of the non-federal entity before the federal government, including the employee's agency, if such representational activity is affirmatively included with the scope of the employee's assignment as determined by the federal agency head.
https://www.justice.gov/file/19571/download