Section 1505 of Title 18, United States Code, as amended by the Victim and Witness Protection Act of 1982, forbids anyone from corruptly, or by threats of force or by any threatening communication, influencing, obstructing, or impeding any pending proceeding before a department or agency of the United States, or Congress. In 1996 Congress enacted a clarifying amendment to 18 U.S.C. § 1515, which defines the term "corruptly" as used in section 1505 to mean "acting with an improper purpose, personally or by influencing another, including making a false or misleading statement, or withholding, concealing, altering, or destroying a document or other information." False Statements Accountability Act of 1996, Pub. L. No. 104-292, §3, 110 Stat. 3459, 3460.
Section 1505 also specifically prohibits anyone from withholding, misrepresenting, removing from any place, concealing, covering up, destroying, mutilating, altering, or by other means falsifying any documentary material, answers to written interrogatories, or oral testimony that is the subject of a proper investigative demand under the Antitrust Civil Process Act, 15 U.S.C. §§ 1311-14, with the intent of avoiding, evading, preventing, or obstructing compliance, in whole or in part, with that demand.
[cited in USAM 9-69.100]