Miller v. Bonta: Assault Weapons Ban Challenge

Miller v. Bonta (originally Miller v. Becerra) challenges the constitutionality of California's assault weapons ban under the Roberti-Roos Assault Weapons Control Act of 1989 and its subsequent amendments, which prohibit the manufacture, sale, and possession of firearms classified as "assault weapons" based on enumerated features ^[1].

California's Assault Weapons Framework

California's assault weapons ban operates through three categories: firearms listed by make and model in Penal Code section 30510 (the original Roberti-Roos list); firearms with specific features such as a pistol grip, thumbhole stock, folding stock, grenade launcher, or flash suppressor on a semiautomatic centerfire rifle with a detachable magazine (PC 30515); and any semiautomatic centerfire rifle with an overall length of less than 30 inches ^[2].

Judge Benitez's 2021 Ruling

On June 4, 2021, Judge Roger Benitez of the Southern District of California issued a sweeping ruling striking down the assault weapons ban. In a 94-page opinion, he found that the banned firearms are "arms" protected by the Second Amendment, that they are commonly owned for lawful purposes, and that the ban fails any level of constitutional scrutiny. The opinion opened with the now-famous line comparing an AR-15 to a "Swiss Army knife," drawing significant media attention and criticism.

Ninth Circuit Stay

The Ninth Circuit immediately stayed Judge Benitez's order pending appeal, keeping the assault weapons ban in effect. The case was briefed and argued before a three-judge panel.

SCOTUS GVR After Bruen

Following the Bruen decision in June 2022, the Supreme Court granted certiorari, vacated the Ninth Circuit's proceedings, and remanded for reconsideration under the new text, history, and tradition framework. The Ninth Circuit in turn remanded to Judge Benitez ^[3].

Post-Remand Proceedings

On remand, Judge Benitez conducted additional proceedings applying the Bruen framework. On October 19, 2023, he again ruled that the assault weapons ban is unconstitutional, finding no historical tradition supporting the prohibition of commonly owned semiautomatic firearms based on cosmetic features. The state appealed, and the case returned to the Ninth Circuit.

Current Status (2025-2026)

Oral arguments were held before a Ninth Circuit three-judge panel on January 24, 2024. The panel deferred its decision pending the outcome of the en banc proceedings in Duncan v. Bonta, which addressed the related question of California's large-capacity magazine ban.

On March 20, 2025, the Ninth Circuit issued its en banc decision in Duncan, upholding the magazine ban in a 7-4 decision. Following the Duncan ruling, the Miller panel ordered supplemental briefing on March 27, 2025, directing the parties to address the impact of the Duncan en banc decision on the assault weapons ban challenge. Supplemental briefs were filed in April 2025, and the case was resubmitted for decision.

As of May 2026, no panel ruling has been issued. The case has been fully resubmitted for decision following the supplemental briefing process. The Duncan holding -- which characterized large-capacity magazines as "optional accessories" rather than "arms" -- may influence the Miller outcome, but the assault weapons ban raises distinct legal questions. Unlike magazines, the items regulated under the assault weapons ban are complete firearms, and Judge Benitez found them "commonly owned for lawful purposes," a characterization that may require different treatment under the Bruen framework. A decision from the three-judge panel is expected, though no date has been set.

The assault weapons ban remains fully enforceable. All existing requirements regarding assault weapon classification, registration, and prohibited features continue to apply while the case is pending.

Significance

Miller v. Bonta is the most significant challenge to any state's assault weapons ban in the post-Bruen era. Its outcome will likely determine the constitutionality of similar bans in other states and could reach the Supreme Court.