Trump administration sues Colorado to overturn ban on large-capacity magazines

The Trump administration moved to put Washington directly in the fight over Colorado gun law, suing the state to overturn a ban on large-capacity magazines that has been in effect since July 1, 2013. The case, filed Wednesday in the U.S. District Court for the District of Colorado, asks a federal judge to strike down a state policy adopted after the 2012 Aurora movie-theater shooting, a massacre that killed 12 people and wounded 58.

At the center of the challenge is Colorado’s rule barring magazines that hold more than 15 rounds, with narrow exceptions for preexisting magazines kept in continuous possession, permanently altered devices, .22 caliber tubular magazines and lever-action tubular magazines. The Justice Department argued that the law reaches magazines that come standard with many popular firearms, including AR-15-style rifles, and said law-abiding Americans own hundreds of millions of the banned magazines. Assistant Attorney General Harmeet K. Dhillon called the statute “political virtue signaling at the expense of Americans’ constitutional right to keep and bear arms.”

The administration is using a legal theory built around the Supreme Court’s District of Columbia v. Heller decision, which held that the Second Amendment protects firearms in common use for lawful purposes. That approach matters because Colorado’s magazine cap has already survived earlier political and legal attacks in different form. In 2016, the 10th U.S. Circuit Court of Appeals dismissed a challenge from a broad coalition that included the Colorado Outfitters Association, the National Shooting Sports Foundation, Magpul Industries and several sheriffs, but the court never reached the Second Amendment question because it ruled the plaintiffs lacked standing.

Colorado officials immediately rejected the federal filing. Attorney General Phil Weiser called it a “dangerous overreach” that would put Coloradans at greater risk of gun violence. The state’s own statutory annotation says the magazine law was upheld as a reasonable exercise of police power aimed at reducing deaths in mass shootings, and that limiting magazines to 15 rounds does not unreasonably burden self-defense.

The suit also arrives as part of a broader federal push against state and local gun restrictions. A day earlier, the Justice Department sued Denver over its assault-weapons ban, and Mayor Mike Johnston responded, “Our answer is hell no.” Together, the cases signal an effort to redraw the line between state police power and federal gun-rights enforcement, with Colorado’s law now serving as a test case for similar magazine-cap restrictions in other states. If the administration prevails, the ruling could ripple far beyond Colorado and reshape how far states can go in limiting the ammunition capacity of widely owned firearms.