18 States and D.C. Ask Supreme Court to Preserve Local Limits on AR-15-Style Rifles

A coalition of 18 states and the District of Columbia, including California, asked the U.S. Supreme Court on Wednesday to preserve the power of states and local governments to restrict AR-15-style rifles, filing a friend-of-the-court brief in a closely watched Second Amendment case that the justices are set to hear in December.

California Attorney General Rob Bonta said he joined the filing in the consolidated cases Viramontes v. County of Cook, No. 25-238, and Eddie Grant, Jr. v. Ronnell Higgins, No. 25-566. The Supreme Court agreed on June 30 to hear the dispute, combined the cases and scheduled arguments for Dec. 2.

At the center of the case is a broad constitutional question the brief frames this way: “Whether the Second and Fourteenth Amendments guarantee the right to possess AR-15 platform and similar semiautomatic rifles.” The states backing Connecticut and Cook County, Illinois, told the court that AR-15-style rifles and similar weapons are “uniquely dangerous” and can be regulated under the Supreme Court’s current Second Amendment test. They also urged the justices to reject the idea that a weapon becomes constitutionally protected simply because it is widely owned.

Bonta’s office said the filing supports lower-court decisions that upheld the Connecticut and Cook County laws as consistent with the Second Amendment. In a statement, Bonta said, “The California Department of Justice will continue to aggressively defend life-saving safety measures and support local leaders with the tools necessary to keep people safe. Assault weapon laws restrict a small and uniquely dangerous category of weapons that have proven to be mass shooters’ weapon of choice for a reason.”

The brief comes at a pivotal moment in gun litigation after the Supreme Court’s 2022 decision in New York State Rifle & Pistol Association v. Bruen. In that ruling, the court said judges reviewing gun laws must ask whether modern restrictions fit within the nation’s historical tradition of firearm regulation. The coalition told the justices that standard allows governments to regulate especially dangerous weapons and supports the assault-weapon restrictions at issue here.

The stakes extend well beyond Connecticut, Cook County or California. The consolidated case is widely seen as the Supreme Court’s first direct merits review of modern state and local bans on AR-15-style rifles and similar semiautomatic weapons. Its outcome could affect laws already in force in multiple states and localities.

The court’s review also follows a growing split in the lower courts. Several federal appeals courts have upheld similar restrictions, but the 3rd U.S. Circuit Court of Appeals in July struck down New Jersey’s assault-firearms and magazine-capacity bans, creating a clear conflict among the courts and increasing pressure on the justices to step in.

The multistate filing, formally captioned “Brief of Massachusetts, New Jersey, 16 Other States, and the District of Columbia as Amici Curiae in Support of Respondents,” underscores how nationally consequential the case has become. When the justices hear arguments in December, they will be weighing not just the fate of two local gun laws, but how much authority states and local governments will retain to regulate assault-weapon-style semiautomatic rifles under the Constitution.