When Gun Rights Meet Marijuana Laws: A Constitutional Collision Course

What happens when America's evolving marijuana laws collide with its gun rights? On March 2nd, the Supreme Court will grapple with this exact question in United States v. Hemani, a case that exposes the constitutional chaos lurking beneath our drug and firearms policies.

The case centers on a deceptively simple question: Can Congress criminalize gun possession by an "unlawful user" of marijuana? But as federal courts have discovered, defining an "unlawful user" is anything but simple.

The Vagueness Problem That Courts Can't Solve

Ali Hemani was charged under federal law for possessing a firearm while being an "unlawful user" of controlled substances. The statute seems straightforward until you try to apply it to real life. Does someone who tried marijuana once in college lose their gun rights forever? What about the person who shares a joint with family on holidays but otherwise abstains?

Federal appeals courts have reached wildly different conclusions. The Third Circuit requires "some regularity" of drug use. The Sixth Circuit demands "sufficiently consistent, prolonged" use close in time to gun possession. The Eighth Circuit says prosecutors need only show drug use "during the period" someone possessed a gun.

This judicial confusion isn't just academic—it creates a constitutional crisis. The Supreme Court has long held that laws violating due process when they're "so vague that [they fail] to give ordinary people fair notice of the conduct [they punish]."

Consider the absurdity: In one federal circuit, a single marijuana use might not qualify someone as an "unlawful user." In another, it could trigger a 10-year federal prison sentence.

The Second Amendment's Impossible Historical Test

The case arrives at a Supreme Court already struggling with its own Second Amendment jurisprudence. In New York State Rifle & Pistol Association v. Bruen (2022), the Court's conservative majority established a new framework requiring modern gun laws to be "consistent with this Nation's historical tradition of firearm regulation."

This sounds reasonable until you realize it demands judges become amateur historians, scouring 18th-century legal codes for "analogous regulations" to modern laws. The results have been predictably chaotic.

In United States v. Rahimi (2024), eight justices upheld a law disarming domestic abusers—despite the fact that no such laws existed in the 1700s, and spousal abuse wasn't even criminalized until 1871. The justices essentially ignored their own historical test when it would have produced an obviously terrible result.

Meanwhile, during oral arguments in Wolford v. Lopez this January, conservative justices signaled they'll strike down Hawaii's law requiring permission to carry guns on private property—despite clear historical precedents from New Jersey, Pennsylvania, and New York in the 18th century.

A Way Out of the Constitutional Maze

The Hemani case offers the Court an elegant escape from this historical morass. Rather than wrestling with whether 18th-century "habitual drunkard" laws somehow justify modern marijuana prohibitions, the justices could simply strike down the law as unconstitutionally vague.

The Trump administration argues the law should apply only to "habitual drug users," attempting to salvage it through historical analogy. But this interpretation only highlights the law's fundamental problem: if even the government can't clearly define who qualifies as an "unlawful user," how can ordinary citizens be expected to know?

The vagueness doctrine offers a principled resolution that doesn't require judges to play constitutional archaeologist or make arbitrary distinctions between occasional and habitual use.

The Broader Stakes for American Justice

This case illuminates a deeper tension in American law. As marijuana legalization spreads—now legal in 38 states for medical use and 21 states for recreational use—federal prohibitions increasingly seem disconnected from social reality.

Yet the gun rights at stake are equally fundamental. The collision between these two areas of law reveals how constitutional interpretation can become divorced from practical governance when courts prioritize ideological consistency over legal clarity.