A new Colorado law restricting gun purchases to people 21 and older is not in effect while a broader lawsuit challenging its constitutionality plays out, a district court judge ruled Monday afternoon.

District Court Judge Philip A. Brimmer granted the preliminary injunction in response to a lawsuit brought by guns-rights organization Rocky Mountain Gun Owners and two Coloradans older than 18 but younger than 21.

In the ruling, Brimmer wrote Gov. Jared Polis “failed to meet his burden to demonstrate that SB23-169 is consistent with the Nation’s historical tradition of firearms regulation.” The individual plaintiffs, he added, “have demonstrated a likelihood of success on the merits” of their case.

In justifying the preliminary injunction, which does not represent a permanent ruling, Brimmer sided with the argument that any possible infringement upon constitutional rights is enough to warrant the hold on enforcing the law.

He cited a 10th Circuit Court of Appeals ruling in Free the Nipple-Fort Collins v. City of Fort Collins that most courts “consider the infringement of a constitutional right enough and require no further showing of irreparable injury.” In that case, plaintiffs successfully argued that a law prohibiting women from going topless in public, while allowing men to do so, violated the Equal Protection Clause of the U.S. Constitution.

This lawsuit challenged the age limit law, as well as another measure that would institute a waiting period for all firearm purchases in the state. The age limit law went into effect Monday. The judge did not rule on the waiting period law, which is slated to go into effect in October. A separate, previous state law prohibiting people younger than 21 from buying pistols appears unaffected by this ruling.

Colorado Democrats earlier this year passed the slate of new gun laws, including regulations on so-called ghost guns and an expansion of who can file extreme risk protection orders under the already existing red flag law. Democrats expanded their majorities in both the state House of Representatives and the state Senate in the last election.

“We told them what they’re doing is unconstitutional and they did it anyway,” Rocky Mountain Gun Owners Executive Director Taylor Rhodes said after the ruling. “They’re costing the state hundreds of thousands or millions of dollars by passing laws that are frivolous.”

Rhodes had pledged in January to sue over any laws his group sees as infringing upon Second Amendment rights, particularly after the higher standard set by the U.S. Supreme Court in its 2021 ruling on New York State Rifle & Pistol Association Inc. v. Bruen.

Rocky Mountain Gun Owners sued the state as soon as Polis signed the bevy of gun laws in April. The group specifically questioned the constitutionality of the laws that would create a three-day waiting period and age limits.

“Since 1968, federal law has required Coloradans to be 21 years old to purchase a pistol, but a loophole allowed kids under age 21 to legally buy a rifle instead,” Polis spokesperson Conor Cahill said in a statement. “This law closes that loophole and the Governor hopes that the courts agree with him that the law is fully consistent with our Second Amendment rights. The Governor is working towards his goal of making Colorado one of the 10 safest states in the country — and the same age requirements for pistols and rifles would help support responsible gun ownership.”

In a statement late Monday, bill sponsors Sen. Kyle Mullica and Majority Leader Monica Duran and Rep. Eliza Hamrick said: “Increasing the age to purchase a firearm to 21 is commonsense policy that will prevent gun violence and keep our communities safe, and we disagree with the judge’s interpretation and are disappointed in the decision. We’re proud of our work this year to pass several new laws that will reduce firearm deaths and save lives by expanding Colorado’s ‘Red Flag Law’, cracking down on ghost guns, holding gun manufacturers accountable and establishing a three-day waiting period to purchase a firearm.”

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