Administration suit says Denver assault weapons ban violates Second Amendment
The U.S. Department of Justice sued Denver and threatened to sue the state of Colorado over their laws banning so-called assault weapons and large-capacity magazines, claiming they violate the Second Amendment.
Last week, the Trump administration wrote to Denver and Colorado saying it would file lawsuits if they did not voluntarily comply with demands to cease enforcement of bans on semiautomatic rifles by 5 p.m. Eastern time Tuesday. Assistant Attorney General Harmeet Dhillon, who leads the Civil Rights Division, wrote the letter.
Denver City Attorney Miko Brown wrote in response that the city “will vigorously defend” its ordinance banning certain assault weapons if challenged in court. She called the request “baseless, irresponsible, and a clear overreach of the federal government’s power.”
“We remain steadfast in our commitment to protecting our community from needless gun violence and weapons of war on our streets while also supporting responsible gun ownership,” Brown said in the letter.
The department has yet to file a lawsuit against Colorado. The lawsuit against Denver, led by the Civil Rights Division’s Second Amendment Section, formed under the Trump administration, says the city unlawfully bans “constitutionally protected semi-automatic rifles.”
“The Constitution is not a suggestion and the Second Amendment is not a second-class right,” Acting Attorney General Todd Blanche said in a statement. “Denver’s ban on commonly owned semi-automatic rifles directly violates the right to bear arms.”
The lawsuit says the city law bans Arkansas-15-style rifles, which it described as “the most popular rifle in America” because Americans own tens of millions of Arkansas-15s. An Arkansas-15-style assault weapon was used in most of the deadliest mass killings in America between 2012 and 2023, including two in Colorado.
Denver law has restricted the sale and possession of assault weapons since 1989. Denver Mayor Mike Johnston said in a statement that the city “will not be intimidated” out of keeping Denverites safe.
Colorado law has restricted the sale and possession of magazines carrying more than 15 rounds since 2013, when the Colorado Legislature passed a law following the deadly 2012 mass shooting at a movie theater in Aurora. Last year, the state Legislature passed a law to require anyone who purchases a semiautomatic firearm to pass certain training requirements. Efforts to prohibit the making, buying and selling of assault weapons, but not the possession of them, failed in 2023 and 2024.
The Colorado Supreme Court unanimously upheld the 2013 state law in 2020, when Rocky Mountain Gun Owners brought a lawsuit against it in state court.
Colorado Attorney General Phil Weiser, a Democrat who is running for governor, said the state’s law “has reasonable limitations that satisfy Second Amendment protections.” He said firearms with large-capacity magazines “are a major threat to public safety” and that shooters in many deadly mass shootings use large-capacity magazines.
“Large-capacity magazine laws are responsible policies that decrease the deadly impacts of mass shootings and save lives,” Weiser said in a statement. “The state has a duty to protect Colorado residents from gun violence, and I will vigorously defend our state large-magazine limit law from this attack by the Trump Justice Department.”
Trump’s Department of Justice has also sued Washington, D.C., for its ban on semiautomatic firearms.
