Supreme Court weighs whether bump stocks qualify as "machine guns" under 1934 statute

The Supreme Court heard argument in Garland v. Cargill over whether non‑mechanical "bump stock" devices used on semiautomatic rifles fit the statutory definition of a "machine gun." Government counsel, Mister Fletcher, told the Court that rifles fitted with bump stocks "do exactly what Congress meant to prohibit when it enacted the prohibition on machine guns," and said the devices can empty a 100‑round magazine in roughly 10 seconds in practice.

Fletcher asked the justices to read the phrase "more than one shot automatically by a single function of the trigger" to capture devices that permit a shooter to initiate and sustain rapid fire through one continuous act. He argued that the bump stock harnesses recoil so that "a single motion both initiates and maintains a multi‑shot sequence," and he cited trial findings and slow‑motion video the government introduced showing the rifle cycling rapidly once the shooter applies steady forward pressure.

Responding to hypotheticals, Fletcher pressed that the statute must be read to prevent easy evasion, warning that narrow readings could legalize a range of workaround devices. He acknowledged longstanding agency classification letters that previously took a different view but said the ATF reassessed those classifications after the Las Vegas shooting and issued a rule that better reflected the statute's meaning.

Counsel for the respondent, Mister Mitchell, urged a different reading. He argued two independent reasons why bump stocks fall outside the statute: first, "a bump‑stock equipped rifle can fire only one shot per function of the trigger because the trigger must reset after every shot"; and second, the non‑mechanical bump stocks at issue contain no self‑regulating mechanism and depend on repeated manual exertion by the shooter. "This is all manual," Mitchell said, "Nothing automatic about that process."

Justices pressed both sides across a series of doctrinal and factual points. Several asked whether the phrase "function of the trigger" refers to what the trigger itself does (the mechanical action inside the firearm) or to an act by a person that causes the trigger to operate. Fletcher urged the Court to rely on contemporaneous usage and later statutory amendments that broadened coverage; Mitchell emphasized grammatical readings that identify the trigger as the statutory subject.

The justices also explored related issues: the mens‑rea standard for criminal prosecution (with reference to Staples), whether the ATF's interpretive rule created unfair reliance problems, and whether Congress — not a court or agency — is the appropriate place to address any gap between statutory text and modern device designs. Fletcher told the Court that the ATF announced it would not prosecute persons who surrendered bump stocks before March 2018 and noted the five‑year statute of limitations for related offenses.

On rates of fire, Fletcher told the Court that some bump devices at issue are represented to fire in the range of roughly 408–650 rounds per minute, placing them near the firing rates of conventional automatic military rifles (about 700–950 rounds per minute) and well above typical semiautomatic rates for most shooters. Both sides, however, agreed that rate of fire is evidence but not the statute's controlling test.

Several justices pressed policy implications. A number of questions reflected concern that a narrow textual reading could permit rapid‑fire devices that produce the same public‑safety harms the 1934 statute aimed to prevent; other justices said the Court's role is limited to interpreting the text Congress enacted and that policy choices belong to Congress.

After rebuttal by the government — in which Fletcher reiterated the government's reading and its public‑safety rationale — the Chief Justice announced that the case was submitted.