39 C.F.R. § 230.23 May an Office of Inspector General employee testify as an expert or opinion witness?
Title 39 - Postal Service
No, an Office of Inspector General employee may not testify as an expert or opinion witness with regard to any matter arising out of the employee's duties or functions at the Office of Inspector General for any party other than the United States, except that in extraordinary circumstances, and where the anticipated testimony will not be adverse to the interest of the United States, the authorizing official may approve such testimony in private litigation. A litigant must first obtain the permission of an authorizing official designated by the Inspector General before designating an Office of Inspector General employee as an expert or opinion witness.
Title 39: Postal Service
PART 230—OFFICE OF INSPECTOR GENERAL
Subpart B—Rules Governing Compliance With Subpoenas, Summonses, and Court Orders by Postal Employees Within the Office of Inspector General Where Neither the Postal Service, the United States, Nor Any Other Federal Agency Is a Party
§ 230.23 May an Office of Inspector General employee testify as an expert or opinion witness?

