29 C.F.R. § 1400.735-19 Influencing Members of Congress.
Title 29 - Labor
No money appropriated to the Service shall be used by any employee of the Service to pay for any personal service, printed or written matter, or other devices intended to influence any Member of Congress regarding any legislation or appropriation before the Congress.
Title 29: Labor
PART 1400—STANDARDS OF CONDUCT, RESPONSIBILITIES, AND DISCIPLINE
Subpart B—Employees: Ethical and Other Conduct and Responsibilities
§ 1400.735-19 Influencing Members of Congress.