In Garland v. Cargill, the Supreme Court has struck down (by a 6-3 vote, split along conservative versus liberal lines) a Trump administration regulation including semiautomatic weapons equipped with so-called bump stocks in the definition of “machine gun” under the National Firearms Act of 1934. The 1934 Act defined a machine gun as “any weapon which shoots, is designed to shoot, or can be readily restored to shoot, automatically more than one shot, without manual reloading, by a single function of the trigger.” A standard semiautomatic weapon requires a succession of distinct trigger pulls, each a “reloading,” that falls outside the statutory definition. A bump stock is a device that increases the rate of those successive trigger pulls through a back-and-forth motion that uses the weapon’s recoil to activate each distinct pull. If speed of firing is the defining feature, there is a puzzle: just how much of an increase in speed is needed to warrant treating the bump stock as a machine gun? Conversely, if the sharp line between a single and multiple firings holds, then the speed of any release does not matter: one trigger pull that produces a hundred bullets makes for a machine gun; a hundred separate (albeit rapid) pulls of the trigger that release a hundred bullets always makes a semiautomatic weapon.

When there’s a need to create a statutory dichotomy, sharp discontinuities are always better than sliding scales. Think of traffic lanes: better to delineate each direction cleanly than permit one lane to gradually meld into the next.

After a mass shooting in Las Vegas on October 1, 2017, none of these refinements seemed to matter. As the Court of Appeals, sitting en banc, noted in striking down the bump stock ban, thereby reversing the panel decision, the killer used “many weapons and utilized many accessories,” including bump stocks, to kill sixty people and wound more than four hundred at a music festival. That incident generated a massive public reaction that ignored these refined textual debates. The ATF issued a notice of proposed rulemaking in March 2018 that led to 186,000 comments, followed by the final rule in December 2018, which included the bump stock into the definition of a machine gun—an interpretation that had been uniformly rejected before the Las Vagas massacre. The administration moved so fast that it “short-circuit[ed] the legislative process,” as the en banc Fifth Circuit said, at a time when substantial majorities in both houses of Congress supported a legislative fix. 

To the political supporters of the bump stock regulation, these distinctions were technicalities. The Cargill decision as attacked in New York City by Mayor Eric Adams and the New York State Attorney General on the grounds that removing this regulatory bar imperiled public safety, even if states like New York continued to ban bump stock use. Other denunciations of Cargill were more pointed: “We’ve seen bump stocks cause immense destruction and violence,” said Esther Sanchez-Gomez, litigation director at Giffords Law Center. “The majority of justices today sided with the gun lobby instead of the safety of the American people. This is a shameful decision.”

There remains a nagging causation question of whether a ban could have prevented the Las Vegas massacre, where news reports said about a dozen of the gunman’s many rifles had been fitted with bump stocks. It is not possible to isolate the number of increased deaths and injuries attributable to the use of these devices. Indeed, even if bump stocks had been banned by law, access to them in the illegal market meant that it was likely that deranged killers could get access to both machine guns and bump stocks. The prohibition that New York and other states have against them is at of uncertain value. Nonetheless, Senate Majority Leader Chuck Schumer has leaped into the fray by introducing legislation to reinstate the ban.

Yet in the court, neither the majority nor the dissent in Cargill conceived of the judicial inquiry as a referendum on the desirability of the regulation. As Justice Alito pointed out, the case has no constitutional overtones. Congress, which had failed to enact appropriate legislation once the bump stock regulation had been adopted, need only do now what it should have done then, thereby giving the new position greater legitimacy than any regulation adopted in haste.  

Justice Sonia Sotomayor, in her impassioned dissent, took the view that the statutory phrase “single function of the trigger” was properly read to mean “a single action by the shooter to initiate a firing sequence.” Her definition echoes that found in the Trump-era regulation that speaks of “functioning as the result of a self-acting or self-regulating mechanism that allows the firing of multiple rounds through a single function of the trigger; and ‘single function of the trigger’ means a single pull of the trigger and analogous motions.” But as a matter of statutory construction, both renditions eliminate the reference to discrete trigger actions. Justice Sotomayor does it by talking about “a single action by the shooter,” and the regulation does it by adding the words “analogous motions.” Both bury the statute’s distinction. Neither party can, moreover, take any comfort from the administrative record, which until the 2017 Las Vegas incident perfectly tracked the statutory language.

At this point, the standard move to rescue the regulation would start with an appeal to the ostensible ambiguity in the statutory language that would open the door to the application of the famous—or infamous—decision in Chevron v. NRDC (1984), which asks the courts to show deference to the administrative agency on the interpretation of an ambiguous statute. The common criticism of this rule is that it means all things to all people, which is how it played out in this case in the lower courts. The Fifth Circuit panel saw no reason to invoke the rule because “bump stocks qualify as machine guns under the best interpretation of the statute.” In the next breath, it noted that three other circuits relied on Chevron deference after they concluded that the definition of a machine gun was ambiguous. The en banc decision, for its part, insisted that it was inappropriate to apply Chevron deference to a criminal statute—Michael Cargill, the case’s namesake, would have been guilty of a criminal offense if he had not turned in his bump stocks under protest. Instead, in its view, the applicable rule of construction is the much debated “rule of lenity” which, as an offset to the severity of the criminal law, construes any unclear or ambiguous language most favorably to the individual defendant—an anti-Chevron canon, as it were.

In general, it is difficult to juggle inconsistent canons to deal with the construction of a single statute, and the first line of defense against that is to push hard on a close reading of the statute to avoid the problem. That approach was deployed to great effectiveness by Justice Clarence Thomas, who explained how the trigger mechanism worked with a series of well-timed diagrams. At this point, one might have expected Sotomayor to follow up the view of those lower courts that used Chevron deference to sustain the statute. But the great surprise of the case is that Chevron was never cited by either the dissent or the majority. Both treated the matter solely as an issue of statutory construction, to be solved by matching up the words of the statute with the words of the legislation. 

There is good reason to do just this. The introduction of Chevron deference has two major defects that apply not just in this case but in literally dozens of other cases that come before the Supreme Court. The first is that Chevron deference allows for the regulation to flip from one interpretation to another given the wisdom —or whim—of a given court. Those flip-flops can take place with no notice, leaving private parties less able to guard against major legal changes. That risk is reduced when changes must be made by statutory amendment, given that it is harder to pass legislation than it is to make an administrative tweak from one permissible interpretation to another. 

The second major defect of Chevron is that the power to flip-flop is tantamount to the power to legislate. That state of affairs threatens the structural safeguards of the separation of powers, which charges Congress and only Congress with legislative power. The Chevron silence in this case should thus be thought of as an omen that once the Supreme Court hears the two notable challenges to Chevron that will be decided this term—Loper Bright Enterprises v. Raimondo and Relentless v. Department of Commerceit will either trim or discard Chevron.

overlay image