by Anthony W. Accurso

The U.S. Court of Appeals for the Sixth Circuit weighed in on the ongoing Circuit split of whether a “bump stock” – placement of which on a semiautomatic rifle enables it to function essentially like a machinegun the possession of which is a criminal offense – is a machinegun “part” under the National Firearms Act of 1934, concluding that the rule of lenity requires the Court to construe the ambiguous statute in question in favor of the defendant.

Section 922(o)(1) regulates “machine­gun[s], and any combination of parts from which a machine gun can be assembled” and defines the term “machinegun” via incorporating by reference the definition contained in 26 U.S.C. § 5845(b), which defines it as any “weapon” that can shoot “automatically more than one shot, without manual reloading, by a single function of the trigger” as well as any “part” that’s “designed and intended solely and exclusively, or combination of parts designed and intended, for use in converting a weapon into a machinegun….”

Up until December 26, 2018, the ATF’s position was that bump stocks are not a machine gun part. However, after the 2018 mass shooting in Las Vegas, Nevada, in which a gunman used bump stocks attached to semiautomatic rifles to kill 58 people and injure roughly 500 more in only 10 minutes, the ATF reversed its decade-long position on bump stocks and promulgated a new agency interpretation of 18 U.S.C. § 922(o)(1), which makes it unlawful to “transfer or possess a machinegun,” classifying bump stocks as a machinegun part. See Bump-Stock-Type Devices, 83 Fed. Reg. 66,514 (Dec. 26, 2018) (“Rule”). 

Scott Hardin, an owner of several bump stocks, challenged the ATF’s authority to regulate bump stocks in this manner, arguing that the statutory definition of machinegun clearly excludes bump stocks. In contrast, the ATF argued that the best interpretation of the statute results in the opposite conclusion. The U.S. District Court for the Western District of Kentucky ruled in the ATF’s favor. Hardin timely appealed.

The Court noted that the Courts of Appeals that have addressed this issue are split on the answer, with the Tenth and D.C. Circuits concluding that a bump stock is included within the definition of a machinegun. See Aposhian v. Barr, 958 F.3d 969 (10th Cir. 2020); Guedes v. Bureau of Alcohol, Tobacco, Firearms and Explosives, 920 F.3d 1 (D.C. Cir. 2019) (per curiam). The Fifth Circuit is on the other side of the divide. See Cargill v. Garland, 57 F.4th 447 (5th Cir. 2023). The Sixth Circuit itself was internally divided, with eight judges concluding that the ATF’s Rule should be upheld and eight judges voting to strike it down. See Gun Owners of Am., Inc. v. Garland, 19 F.4th 890 (6th Cir. 2021) (en banc). In total, there have been 22 opinions examining this issue, the Court observed, yet, many reasonable minds disagree on the answer.

The Sixth Circuit’s ruling came by way of three steps. First, the statute was declared ambiguous because it is “subject to more than one reasonable interpretation.” Donovan v. FirstCredit, Inc., 983 F.3d 246 (6th Cir. 2020). The Court based its conclusion on the division amongst the Courts of Appeals, “the ATF’s own flip-flop in its position,” and the arguments by the parties to the case. “Although both parties argue the statutory language is plain and unambiguous, both also argue that the plain meaning supports their interpretation. This indicates ambiguity. Furthermore, the existence of divergent Court opinions also suggests ambiguity.” Quoting Pugliese v. Pukka Dev., Inc., 550 F.3d 1299 (11th Cir. 2008).

Second, when a statute is ambiguous and an agency’s rule is a “permissible construction of the statute,” the agency’s rule is generally given deference under Chevron, USA, Inc. v. NRDC, 467 U.S. 837 (1984). However, the ATF declined to invoke the so-called “Chevron deference,” believing that deference analysis was unnecessary presumably because, in its view, the statute is not ambiguous.

Further, the Court explained that the Supreme Court’s dicta from two more recent cases suggest Chevron deference should not be applied to criminal statutes. “The court has never held that the government’s reading of a criminal statute is entitled to any deference.” United States v. Apel, 571 U.S. 359 (2014). And, “criminal laws are for courts, not for the government, to construe.” Abramski v. United States, 573 U.S. 169 (2014).

A knowing violation of 18 U.S.C. § 922(o)(1) is punishable by up to 10 years of imprisonment. § 924(a)(2). Comparing that criminal sanction to the statute’s only civil requirement – registration of the weapon – and it is clear that the statute “has a predominantly criminal scope,” according to the Court.

Chevron deference was created to defer to an agency’s personnel with expertise “in a complex field of regulation with nuances perhaps unfamiliar to the federal courts.” Dolfi v. Pontesso, 156 F. 3d 696 (6th Cir. 1998). This is appropriate for “highly technical and complex securities, tax, workplace safety, and environmental law regimes” but less appropriate for “the distribution of dangerous drugs, the commission of violent acts, or, as relevant here, the possession of deadly weapons,” the Court explained, adding that these “are areas in which the courts are well-equipped to operate, and we see no reason why we should abdicate our interpretive responsibility in such instances.” Therefore, the Court concluded that Chevron deference does not apply to the ATF’s Rule because the underlying statute is “predominantly” criminal in scope.

After deciding the statute’s definition of machinegun parts is ambiguous and that the ATF’s Rule is owed no deference, the Court’s third step was to apply the “rule of lenity.”

“When Chevron difference is not warranted and standard principles of statutory interpretation ‘fail to establish that the government’s position is unambiguously correct, we apply the rule of lenity and resolve the ambiguity in [the criminal defendant’s] favor.’” Quoting United States v. Granderson, 511 U.S. 39 (1994).

Based on the foregoing reasons, the Court ruled in Hardin’s favor, deregulating bump stocks in its jurisdiction. It then closed with a quote from the Fifth Circuit: “Bump stocks may well be indistinguishable from automatic weapons for all practical purposes. But … it would be dangerous … to punish a crime not enumerated in the statute, because it is of equal atrocity, or of kindred character, with those which are enumerated.” Cargill v. Garland, 57 F.4th 447 (5th Cir. 2023) (en banc) (Ho, J., concurring).

Thus, because the statutory scheme at issue “does not clearly and unambiguously prohibit bump stocks,” the Court held that the rule of lenity requires it to construe the statute in Hardin’s favor.

Accordingly, the Court reversed the judgment of the District Court and remanded for further proceedings consistent with its opinion. See: Hardin v. BATFE, 65 F.4th 895 (6th Cir. 2023).