In any action, suit, or proceeding in a court of the United States, to which the United States or an agency or employee thereof is not a party, the court is required to certify to the Attorney General when the constitutionality of an Act of Congress is called into question, and the court must permit the United States to intervene to submit evidence or argument on the issue of constitutionality. See 28 U.S.C. § 2403. The Civil Division (or ENRD, for environmental statutes) should be promptly advised of any case in which the United States Attorney learns that the pleadings challenge the constitutionality of an Act of Congress, a regulation or any other federal action.

[updated April 2018]