Code of Federal Regulations Title 43. Public Lands:  Interior § 43.3000.3 Unlawful interests

No member of, or delegate to, Congress, or Resident Commissioner, and no employee of the Department of the Interior, except as provided in 43 CFR part 20, shall be entitled to acquire or hold any Federal lease, or interest therein. (Officer, agent or employee of the Department—see 43 CFR part 20;  Member of Congress—see R.S. 3741;  41 U.S.C. 22;  18 U.S.C. 431–433.)