WASHINGTON – In the United States, gun rights and cannabis legalization often occupy opposite ends of the political spectrum. Yet both have significantly influenced the nation’s landscape over recent decades.

In an unexpected intersection, these two issues converge in a case set for Supreme Court review on Monday. This case has created some surprising alliances.

The Trump administration, typically associated with gun rights, will be defending a firearm restriction in this instance, receiving support from gun-control advocates who usually align with Democratic interests.

Meanwhile, an alliance between the National Rifle Association and the American Civil Liberties Union stands in opposition.

The central issue at hand is a federal law that prohibits individuals who regularly use marijuana from legally possessing firearms. This matter has sparked division among lower courts, especially following a significant 2022 Supreme Court ruling that broadened gun rights.

Cecillia Wang, the legal director of the ACLU, argues that the law infringes upon the Second Amendment and is unconstitutionally vague regarding the definition of a drug user.

“We’re deeply concerned with the potential of this statute to basically give federal prosecutors a blank check,” she said. “Millions of Americans use marijuana and there is no way for them to know based on words of this statute whether they could be charged or convicted of this crime because they own a firearm.”

Cannabis is legal for medicinal use in most states and for recreational use in about half the country.

But the law also applies more widely against all illegal substances, meaning the case could allow broader legal gun use by other drug users. The group Everytown for Gun Safety said the law meets the Supreme Court’s requirement that gun laws must have a strong grounding in the nation’s history and tradition.

“Restricting firearm use by illegal drug users is ‘as old as legislative recognition of the drug problem itself,’” attorneys wrote.

Cannabis remains illegal on a federal level, though President Donald Trump has signed an order to fast-track its reclassification as a less dangerous drug.

His Justice Department is also asking the justices to revive a criminal case against Ali Danial Hemani, a Texas man who was charged with a felony because he had a gun in his house and acknowledged smoking marijuana every other day. FBI agents also found a small amount of cocaine when they searched his home as part of a broader investigation, but the gun charge was the only one filed against him.

The conservative-leaning 5th U.S. Circuit Court of Appeals rejected the case, finding that only people who are intoxicated while armed can be charged with a crime.

The administration has argued in favor of gun rights in other cases, but government lawyers say this law is a justifiable restriction. “Habitual illegal drug users with firearms present unique dangers to society — especially because they pose a grave risk of armed, hostile encounters with police officers while impaired,” they wrote in court documents. The law fits within the nation’s history of restrictions on people who were frequently drunk, they argued.

While the conservative-majority Supreme Court has expanded gun rights, it also has upheld a federal law disarming people who are subject to domestic violence restraining orders. The Department of Justice argues that drug users are similarly risky. The law it is asking the court to uphold was also used in the case of Hunter Biden, who was convicted of buying a gun when he was addicted to cocaine.

But the NRA and other gun-rights groups, typically aligned with the GOP, are arrayed against the administration in Hemani’s case.

“Americans have traditionally chosen which substances are acceptable for responsible recreational use, and the fundamental right to keep and bear arms was never denied to people who occasionally partook in such drugs — unless they were carrying arms while actively intoxicated,” lawyers for the Second Amendment Foundation wrote in court documents.

The cannabis group NORML agrees, saying one of the fastest-growing groups of users are baby boomers trying products such as marijuana gummies to relieve arthritis and sleep problems.

“It’s laughable to think that by outlawing cannabis users possessing firearms you’ll minimize the problem with gun violence,” said Joe A. Bondy, chair of the board of directors for NORML, one of the country’s oldest and largest groups advocating for the legalization of marijuana.