Colorado Magazine BanWhat the 2026 DOJ lawsuit means

The Colorado magazine ban is now in the federal government’s crosshairs, and unlike the Denver lawsuit making headlines alongside it, this one reaches every gun owner in the state. On May 6, 2026, the Department of Justice sued the State of Colorado over its limit on magazines that hold more than 15 rounds, one day after filing a separate suit against Denver’s assault weapons ordinance.

The DOJ’s new Second Amendment Section argues the 15-round cap violates the Constitution. The state intends to defend it. While the two sides fight it out in court, the law itself has not changed, and that matters for anyone in Douglas County who buys, sells, or carries magazines. Here at Franktown Firearms, we field questions about magazine limits at the counter constantly, so here’s the plain-English breakdown of what was filed, where the law came from, and what it means for you right now.

The lawsuit was filed on May 6, 2026, against the State of Colorado and the Colorado Department of Public Safety, whose divisions, the State Patrol and the Colorado Bureau of Investigation, enforce the rule. It targets Colorado Revised Statute 18-12-302, which makes it a crime to sell, transfer, or possess a magazine capable of holding more than 15 rounds.

The federal argument runs through the same legal channel as the Denver case. The DOJ contends that magazines holding more than 15 rounds are standard equipment on many of the most popular firearms in the country, including AR-15-style rifles and a number of semiautomatic pistols, and that tens of millions of them are lawfully owned nationwide. Because those magazines are, in the government’s words, in common use for lawful purposes, the DOJ argues they fall under Second Amendment protection. The complaint also pushes back on the phrase “large-capacity,” calling it politically loaded language for what it says are standard-capacity magazines.

In practical terms, the DOJ is asking a federal judge for two things: a declaratory judgment that the Colorado magazine ban is unconstitutional, and a permanent injunction that would stop the state from enforcing it. The eleven-page filing leans heavily on the Bruen framework, the same Supreme Court test driving the Denver case.

To understand the Colorado magazine ban, you have to go back to 2013. The limit was passed by a Democratic-controlled legislature and signed into law by then-Governor John Hickenlooper, who now serves as one of Colorado’s U.S. senators. It came in the wake of the 2012 Aurora movie theater shooting, one of the deadliest mass shootings in state history, and supporters framed it as a direct response to that tragedy.

The law landed with serious political fallout. Two state legislators who backed it were recalled by voters, and a third resigned rather than face a recall, a sequence that remains one of the most dramatic gun-policy episodes in recent Colorado history.

Colorado is also somewhat unusual in how its limit is structured. According to the Giffords Law Center, fourteen states plus Washington, D.C., restrict magazine capacity, but most of those caps came bundled into broader assault weapons bans, and most set the limit at 10 rounds. Colorado is one of only a handful of states, along with Oregon, Rhode Island, and Vermont, that capped magazine capacity on its own rather than as part of a wider ban, and it set the line at 15 rather than 10. That standalone structure is part of what makes it a distinct legal target.

This is a real legal dispute, not a settled question, and it helps to understand both positions. The DOJ’s case rests on the idea that the Second Amendment protects arms in common use, a principle from the 2008 Heller decision, combined with the 2022 Bruen test that asks whether a restriction fits the nation’s historical tradition of firearm regulation. The government argues that because standard-capacity magazines are owned by the tens of millions and used for target shooting, collecting, and self-defense, banning them restricts protected conduct.

Colorado Attorney General Phil Weiser sees it the opposite way. He has called the lawsuit a dangerous overreach and pledged to defend the law vigorously, arguing that magazine limits are responsible public-safety policy that reduces casualties in mass shootings without violating the Second Amendment. Weiser, who is running for governor, frames the state’s duty as protecting residents from gun violence.

Courts in different parts of the country have split on questions like these, which is exactly why this case could take a long time and may ultimately depend on appellate rulings. Nothing here is legal advice, and if you have questions about your specific situation, talk to a Colorado attorney who handles firearms law.

Here’s the key difference between this case and the Denver one. The Denver assault weapons ban is a city ordinance that never applied in Douglas County. The Colorado magazine ban is state law, which means it applies everywhere in the state, including Franktown, Castle Rock, Parker, and Elizabeth. This is the lawsuit that actually touches your range bag.

And here’s the part people get wrong: a lawsuit being filed does not change the law. The 15-round limit is still in effect today and will stay in effect unless and until a court orders otherwise. That means the rules on buying, selling, and possessing magazines in Douglas County have not moved. On top of that, SB 25-003 adds its own statewide requirements on covered semiautomatic firearm purchases starting August 1, 2026, so there are two separate state-level changes worth tracking. The smart move is to stay current and stay compliant rather than act on a headline.

It’s tempting to read a federal lawsuit as a green light, but that’s a mistake that can get you crosswise with the law. Until a judge actually rules, the Colorado magazine ban stands, and the State Patrol and CBI continue to enforce it. Treat the current limit as the current limit.

If you’re buying magazines, stick to compliant capacities and keep your receipts. If you already own older magazines, understand how the possession rules apply to your situation, and when in doubt, ask. This is the kind of thing our staff handles every day, and we’d rather answer a question at the counter than have a customer guess wrong.

Beyond the legal side, the best use of your energy right now is range time. Court cases move on their own schedule, but your skills are something you control. Whether it’s pistol fundamentals, rifle work, or keeping your CCW current, training is the one part of this that pays off no matter how the lawsuit lands. Stay legal, stay sharp, and let the lawyers argue.