Whether courts should defer under Chevron to an agency interpretation of federal law when the federal government affirmatively disavows Chevron deference

QUESTIONS PRESENTED Since this Court’s 1984 decision in Chevron U.S.A., Inc. v. Natural Resources Defense Council, Inc., 467 U.S. 837 (1984), federal courts have deferred under certain circumstances to reasonable agency interpretations of ambiguous statutory terms. The question of statutory construction at the root of this case is the meaning of the term “machinegun,” a term defined at 26 U.S.C. § 5845(b). In 2018, the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) reversed course and issued regulations that reinterpreted “machinegun” more expansively than it had previously. The court of appeals upheld the regulations, deferring under Chevron to ATF’s statutory interpretation despite the fact that (1) the federal government repeatedly insisted that its interpretation was not entitled to Chevron deference, and (2) almost all of Section 5845(b)’s applications call for criminal sanctions. The Questions Presented are: (1) Whether courts should defer under Chevron to an agency interpretation of federal law when the federal government affirmatively disavows Chevron deference. (2) Whether the Chevron framework applies to statutes with criminal-law applications. (3) Whether, if a court determines that a statute with criminal-law applications is ambiguous, the rule of lenity requires the court to construe the statute in favor of the criminal defendant, notwithstanding a contrary federal agency construction.