Since the Supreme Court upended the standard for determining the constitutionality of gun laws in 2022, defining common use has become hugely important, particularly in cases involving so-called hardware bans, such as prohibitions on AR-15 style rifles and HCMs. Those who oppose such bans argue that common ownership equals common use. Supporters argue that the right measure is the frequency with which a weapon is actually used for self-defense, as the Supreme Court’s Second Amendment jurisprudence is centered on the right of self-defense.
Both sides in the Oregon case agreed that Americans own many millions of HCMs. Given the sheer number of guns produced that are designed to accept them, it follows that large numbers of high-capacity magazines are in circulation. The term high-capacity magazine has no universally accepted definition, but typically is applied to those that hold ten rounds or more (though many models hold 30, 40, 50 or even more rounds). Fourteen states have outlawed HCMs. In at least five of those states, the bans are being challenged. Ten states prohibit AR-15-style rifles, and in at least six, gun rights interests are seeking to strike down the bans.
Judges hearing these challenges have reasoned differently on the “common use” issue. [U.S. District Court Judge Karin] Immergut, placing herself firmly on the frequency side of the debate, cited evidence suggesting that few rounds are fired in the overwhelming majority of defensive gun use cases. She ruled that “features unique” to HCMs — chiefly the ability to fire more than ten rounds without reloading — are rarely employed in self-defense situations, hence they can be banned.
On September 22, U.S. District Court Judge Roger Benitez overturned — for a second time — California’s HCM ban, which voters approved in 2016. Benitez, a gun rights darling who has been criticized for callousness and a lack of restraint, decided that the criterion for common use was simple prevalence. The NSSF chart featured as evidence in the case. “A person may happily live a lifetime without needing to fire their gun in self-defense,” Benitez wrote. “But that is not to say that such a person does not use their gun for self-defense when he or she keeps it under the bed with a hope and a prayer that it never has to be fired.”
— Will Van Sant in The Gun Industry’s Trade Group Is Using Flimsy Data in Big Court Cases