49 CFR § 386.3 - Separation of functions.
(a) Civil penalty proceedings will be prosecuted by Agency Counsel who represent the Field Administrator. In Notices of Violation, the Field Administrator will be represented by Agency Counsel.
(b) An Agency employee, including those listed in paragraph (c) of this section, engaged in the performance of investigative or prosecutorial functions in a civil penalty proceeding or in a proceeding under § 386.11, § 386.72, or § 386.73 may not, in that case or a factually related case, discuss or communicate the facts or issues involved with the Agency Decisionmaker, Administrative Law Judge, Hearing Officer, or others listed in paragraph (d) of this section, except as counsel or a witness in the public proceedings. The prohibition in this paragraph (b) also includes the staff of those covered by this section.
(c) The Deputy Chief Counsel, Assistant Chief Counsel for Enforcement and Litigation, and attorneys in the Enforcement and Litigation Division serve as enforcement counsel in the prosecution of all cases brought under this part.
(d) The Chief Counsel, the Special Counsel to the Chief Counsel, and attorneys serving as Adjudications Counsel advise the Agency Decisionmaker regarding all cases brought under this Part.
(e) Nothing in this part shall preclude Agency Decisionmakers or anyone advising an Agency Decisionmaker from taking part in a determination to launch an investigation or issue a complaint, or similar preliminary decision.