A federal judge has now ruled that commonly-owned ammunition magazines do not fall under the Second Amendment’s protection. How she arrived at that conclusion may catch the Supreme Court’s eye.

Late last week, U.S. District Judge Karin Immergut, a Trump appointee, upheld Oregon’s ballot-initiated Measure 114. That law bans the possession and sale of magazines capable of holding more than ten rounds of ammo and institutes a permitting requirement to purchase a firearm. Immergut found that not only did the nation’s historical tradition of gun regulations support a ban on “Large-Capacity Magazines” (LCMs), but the Second Amendment’s plain text itself did not cover them.

“The evidence in the record illustrates that LCMs are not necessary for firearms to function and are not commonly used for self-defense,” Immergut wrote in her decision. “Because this Court finds that the Second Amendment’s plain text does not cover LCMs, BM 114’s restrictions on LCMs are constitutional.”

While Immergut is not the first federal judge to uphold a magazine ban after the Supreme Court’s ruling in New York State Rifle and Pistol Association v. Bruen, she is one of the first to do so by saying that they fall entirely outside the scope of the Second Amendment’s text. Before even arriving at the main part of the test outlined in Bruen, Immergut concluded that a ban on a commonly-owned firearm accessory, which typically comes standard with the purchase of most modern firearms, could pass constitutional muster.

It’s an analysis that essentially short-circuits Bruen, applied to one of the most hotly-contested policies in all of gun politics. If it catches on, it could have significant policy ramifications for blue jurisdictions nationwide searching for a legal basis to target disfavored magazines and other firearms hardware.

But it’s one that could also run into trouble at the Supreme Court.

In its Heller decision, the Court determined that the Second Amendment’s plain text protects arms “typically possessed by law-abiding citizens for lawful purposes.” The court further clarified the scope of this protection by drawing on the 1939 decision in United States v. Miller, stating, “Miller’s holding that the sorts of weapons protected are those ‘in common use at the time’ finds support in the historical tradition of prohibiting the carrying of dangerous and unusual weapons.”

This “common use” standard applies to the first prong of the Bruen test, which stipulates that “when the Second Amendment’s plain text covers an individual’s conduct, the Constitution presumptively protects that conduct.”

Judge Immergut’s decision quoted from Heller and Bruen about the Second Amendment’s text protecting weapons “in common use at the time” and “commonly used for lawful purposes.” But it also stitched together past comments from the justices on self-defense being the “central component” of the amendment to determine that defense was the only “lawful purpose” worth considering when evaluating the use of so-called large capacity magazines.

“This Court acknowledges that there may be lawful purposes other than self-defense for which an individual can use a firearm,” Immergut wrote. “While these uses may be lawful, they have never been explicitly recognized as being ‘the central component’ of the Second Amendment right; only self-defense enjoys that kind of unique focus within the Supreme Court’s caselaw. Accordingly, this Court finds that the Second Amendment protects an individual right to commonly used firearms for the central purpose of self-defense.”

Then, after removing all consideration of separate lawful activities where a magazine may be used by a gun owner, such as target shooting or hunting, she further whittled down the scope of what constitutes “common use for self-defense” by disregarding gun owners’ stated intent for selecting said magazines. Instead, she considered only documented defensive gun uses featuring large-capacity magazines.

“This Court finds that an individual’s subjective intent in purchasing a firearm or firearm accessory for self-defense, while relevant, also cannot be dispositive in assessing whether a firearm or firearm accessory is in common use for self-defense,” she wrote.

Immergut said that the plaintiffs failed to prove during trial that gun owners commonly needed eleven or more rounds for self-defense. Instead, the evidence Immergut found compelling was the testimony of a researcher who said she analyzed defensive gun use encounters documented by the NRA’s Armed Citizens Database, which simply aggregates publicly-available news stories of defensive gun uses. That researcher claimed an individual fired more than ten rounds in just two of the hundreds of incidents occurring over the period examined, though self-defense stories often don’t mention the number of rounds fired in an incident. Still, Judge Immergut concluded the report was enough evidence of an “objective standard” to show that “having more rounds does not facilitate self-defense.”

“Plaintiffs have not shown that LCMs are commonly employed for self-defense. Defendants have produced credible evidence showing that they are not,” she said. “This Court accordingly finds that the Second Amendment does not protect LCMs.”

This logic is one the Supreme Court could find fault with. It relies on a distinction between the “subjective” reasons why gun owners say they acquire and use a particular regulated item, and on supposedly “objective” metrics of them actually being used in self-defense incidents. It is a distinction the Supreme Court does not appear willing to make, at least if its ruling in Heller is any guide.

“It is no answer to say, as petitioners do, that it is permissible to ban the possession of handguns so long as the possession of other firearms (i.e., long guns) is allowed,” Justice Antonin Scalia wrote in the majority opinion. “It is enough to note, as we have observed, that the American people have considered the handgun to be the quintessential self-defense weapon. There are many reasons that a citizen may prefer a handgun for home defense: It is easier to store in a location that is readily accessible in an emergency; it cannot easily be redirected or wrestled away by an attacker; it is easier to use for those without the upperbody strength to lift and aim a long gun; it can be pointed at a burglar with one hand while the other hand dials the police. Whatever the reason, handguns are the most popular weapon chosen by Americans for self-defense in the home, and a complete prohibition of their use is invalid.”

In other words, an empirical demonstration of handguns specifically being used in the home for defense was not necessary for the Court to find that they are protected by the Second Amendment. It is sufficient to demonstrate through the revealed consumer preferences of gun owners that a given arm is “commonly used” for a lawful purpose like self-defense. And under that standard, it’s hard to see how large-capacity magazines do not similarly fall into that category.

The 2021 National Firearms Survey conducted by Georgetown professor William English, considered to be one of the largest and most comprehensive surveys of U.S. gun ownership, found that 48 percent of gun owners—or 39 million adults—said they’ve owned one or more magazines that hold more than ten rounds. Home defense and recreational target shooting were the two most common reasons indicated for owning the magazines.

Presumably, an accessory ostensibly owned by tens of millions of adults for home defense and recreational shooting would clear the bar of being “commonly used for lawful purposes.” But under Judge Immergut’s version of the “common use” analysis, it’s hard to see how almost any subcategory of firearm or accessory could not similarly be interpreted as being outside the scope of the Second Amendment. Possibly including ammunition magazines of nearly any size.

Given the current makeup of the Supreme Court, that’s not likely to be allowed to stand.

While the ruling is, for now, just one decision at the District Court level, there’s reason to think it has the potential to be influential. Second Amendment jurisprudence is still in its infancy under the new Bruen standard, and courts are still working out how to handle such cases as states continue passing new laws and advocates challenge them in court. Other judges, particularly those looking to find ways of upholding gun laws, will be taking note of any high-profile rulings doing so to date. It also now awaits review in the Ninth Circuit, which is prone to upholding gun laws. If the Ninth Circuit is sympathetic to Immergut’s analysis when it reaches its decision, it could reach a whole new level of visibility and precedential value.

If so, the Supreme Court will have to decide whether to step in and further clarify its view of what is and isn’t “in common use.”