Harmeet Dhillon, assistant attorney general for the Justice Department's Civil Rights Division, took the rare step of appearing before a federal appeals court in a key Second Amendment case even though the DOJ is not a party to the lawsuit.

The case is Barnett v. Raoul, a National Rifle Association-backed challenge to Illinois’ ban on semiautomatic weapons and high-capacity magazines.

In a five-minute appearance before the U.S. Court of Appeals for the 7th Circuit on Monday, Dhillon argued against the 2023 Illinois law signed by Gov. JB Pritzker in the aftermath of the July 4, 2022, Highland Park mass shooting. The measure outlaws AR-15 sales and limits magazines to 10 rounds for rifles and 15 for handguns.

“The federal interest is significant,” Dhillon argued, adding that a lower court’s decision to uphold the law was based on a flawed interpretation of Supreme Court precedent, namely, New York State Rifle & Pistol v. Bruen.

“Firearms in common civilian use are clearly protected, and the court cannot sidestep that by calling them ‘dangerous’ or ‘unusual,’” Dhillon told the court, adding that the federal duty requires the Second Amendment to be “not treated as a second-class right.”

Judge Frank Easterbrook, a Reagan appointee, pressed Dhillon on whether lower court factual findings — such as public safety evidence — might alter her constitutional view. Dhillon replied they would not, while noting that “facts matter in law, but under Bruen, history, not balancing tests or policy determinations, guides constitutional analysis.”

“We have four essentially identical cases pending before district judges in this circuit,” Easterbrook said. “And one thing that worries me is, what happens if they don’t agree with each other? I just find it difficult to believe that the same statute could be constitutional in northern Illinois but not in southern Illinois,” he added. “Or in Illinois, but not Iowa. You get the problem.”

“I do understand the problem,” Dhillon said. “And it is a challenge.”

The Illinois Attorney General’s office, headed by Democrat Kwame Raoul, defended the ban. Their argument: the banned weapons are akin to military firearms and therefore outside constitutional protection.

Dhillon’s personal courtroom argument was notable and rare, as she would typically file amicus briefs on behalf of a party, the NRA in this case, rather than appearing in person.

Newsmax wires contributed to this report.