On April 28, 2026, Assistant Attorney General Harmeet Dhillon sent a letter to Denver Mayor Mike Johnston and City Attorney Miko Brown that deserves to be framed on the wall of every Second Amendment organization in America. The message was unambiguous: Denver’s 37-year-old assault-weapon ordinance — which bans all semi-automatic pistols and centerfire rifles with detachable magazines holding more than fifteen rounds, including AR-15-style rifles — violates the Second Amendment. Stop enforcing it, acknowledge it is unconstitutional, and enter a consent decree before 5 p.m. today, or the Department of Justice will sue. Denver said no. Now there will be a federal lawsuit.
The Civil Rights Division Finally Treats the Second Amendment as a Civil Right
Here is what makes this action historically extraordinary: the demand came from the Civil Rights Division of the Department of Justice — the same division that enforces the Civil Rights Act, the Voting Rights Act, and the Fair Housing Act. For as long as I have been doing this work, the argument from the constitutional law side has been that the Second Amendment is a civil right deserving the same aggressive federal enforcement as every other enumerated right. The Trump DOJ, through Dhillon — confirmed by the Senate in April 2025 and sworn in by Attorney General Pamela Bondi — has made that argument official federal policy.
The Dhillon letter does not meander. It invokes District of Columbia v. Heller, 554 U.S. 570 (2008), directly and precisely: “Law-abiding Americans own and use for lawful purposes literally tens of millions of AR-15 style rifles. Indeed, it is the most popular rifle in America. The City has banned an arm in common use for lawful purposes by law-abiding citizens. Therefore, the Ordinance violates the Second Amendment.” That is Heller’s “in common use” test stated plainly and applied to a municipal ordinance. No hedging, no carve-outs, no government-lawyer circumlocutions. The Civil Rights Division is treating a gun ban as a civil rights violation. That is where my read of the Constitution has always led. It is gratifying — and long overdue — to see the DOJ arrive there too.
Denver’s 37-Year Ordinance Cannot Survive Heller or Bruen
Denver’s assault-weapon ordinance dates to 1989, enacted after a violent-crime spike prompted the chief of police to push City Council to act. I understand the political pressures of that moment. But what a city council could plausibly attempt in 1989, before Heller and before New York State Rifle & Pistol Ass’n v. Bruen, 597 U.S. 1 (2022), is not what it can constitutionally do today.
Denver Code Section 38-130 defines an “assault weapon” as any semi-automatic pistol or centerfire rifle equipped with a detachable magazine of more than fifteen rounds. Under that definition, a standard AR-15 configured with a thirty-round magazine — the configuration owned by an estimated thirty million law-abiding Americans for home defense, competition, and recreational shooting — is flatly banned inside Denver city limits. That configuration is precisely what Heller’s “in common use” test protects. The Supreme Court in Caetano v. Massachusetts, 577 U.S. 411 (2016), unanimously reinforced that “in common use” is a broad protection covering arms that are widely owned and lawfully used — a category the AR-15 fits so clearly that the argument should not be close.
Bruen layered on the historical-tradition requirement: to sustain a firearms regulation, the government must demonstrate that the regulation is consistent with this nation’s historical tradition of firearm regulation. There is no founding-era tradition of banning the most popular long gun in civilian circulation. Denver cannot produce one. Mayor Johnston’s public retort — “Denver’s law has stood for 37 years because it works, it saves lives, and it reflects the values of our community” — is precisely the interest-balancing the Supreme Court forbids. Heller rejected that mode of analysis explicitly. The Second Amendment is not a policy preference to be weighed against local crime statistics. It is a constitutional right. The DOJ is correct to say so.
Defiance, a Deadline, and What Comes Next
Dhillon did not merely ask Denver to stop enforcement. She demanded a consent decree — a formal judicial order acknowledging the unconstitutionality of the ordinance and committing the city never to enforce it again. City Attorney Miko Brown’s response called the demand “baseless, irresponsible, and a clear overreach of the federal government’s power.” That response tells me everything: Denver intends to litigate.
The DOJ’s lawsuit will land in the U.S. District Court for the District of Colorado, within the Tenth Circuit. The Tenth Circuit has not issued a definitive ruling on municipal assault-weapon bans under Bruen’s historical-tradition standard. This case will put that question squarely before the circuit and, in all likelihood, before the Supreme Court. Denver’s choice to fight has accelerated a confrontation the country was heading toward regardless.
This is not an isolated action. When Virginia Governor Abigail Spanberger signed her state’s assault-firearms ban into law last month, Dhillon issued an identical threat. The Civil Rights Division is deliberately constructing a national docket of Second Amendment enforcement actions, treating each gun ban as a civil rights violation demanding federal response. That is the right legal theory, and it is the argument I have made in my scholarship for years.
Denver had a choice. It chose defiance. A federal judge in Colorado will now rule on whether a city ordinance enacted before Heller can survive the constitutional standards Heller and Bruen established. My read: it cannot.
This article is based on analysis by Professor Mark W. Smith, constitutional attorney and Host of the Four Boxes Diner 2nd Amendment channel. Watch the original video here. This does not constitute legal advice.