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Knives Out

How This Knife Could Upend Restrictions on Weapons All Across the Nation

A federal appeals court ruling could have a massive impact on the future of gun safety in America.

Heuser/Ullstein Bild/Getty Images
A Hawaii law created an absolute ban on butterfly knives like this one, but a recent court ruling could overturn that restriction—along with many others.

The Second Amendment is arguably the most interesting area of American constitutional law right now. Courts and judges have already spent more than two centuries defining the scope of what counts as free speech under the First Amendment and probable cause under the Fourth Amendment. But they did not spend much time on defining what the individual right to bear arms protects. How could they have? The Supreme Court only established it within the last 15 years.

One of the many big questions in this brave new world is deceptively complicated: What exactly counts as “arms” that someone can bear under the Second Amendment? (Please, no jokes about ursine limbs.) On Monday, the Ninth Circuit Court of Appeals came one step closer to answering that question in Teter v. Lopez. The case involved a challenge to Hawaii’s absolute ban on possessing butterfly knives, a type of small knife with a bifurcated handle that folds upward to cover the blade when sheathed. As the court noted, an experienced user can quickly unfold it with one hand if the need arises.

Nearly all Second Amendment cases involve firearms. But the three-judge panel ruled that the same logic that protects guns under the individual right to bear arms applies to other types of weapons. “Because the possession of butterfly knives is conduct protected by the plain text of the Second Amendment, and because Hawaii has not demonstrated that its ban on butterfly knives is consistent with this Nation’s historical tradition of regulating arms, we conclude that section 134-53(a) violates Plaintiffs’ Second Amendment rights,” Judge Carlos Bea wrote for the court.

That an absolute ban on a certain type of knife has been judged unconstitutional might seem like a small matter at first glance. But Monday’s ruling could directly affect a wide swath of gun and weapon regulations in the Ninth Circuit’s jurisdiction, which covers most of the Western United States and roughly one-fifth of the national population. Its reasoning, if adopted by other courts, could also make it much more difficult for state and federal lawmakers to restrict access to certain types of weapons.

The case comes from a lawsuit filed by two men, Andrew Teter and James Grell, who live in Hawaii and want to purchase butterfly knives for self-defense. Barring their path is a state law that makes it a misdemeanor offense whenever someone “knowingly manufactures, sells, transfers, possesses, or transports” a butterfly knife in Hawaii. Teter and Grell attested that they owned butterfly knives before moving to Hawaii and had to dispose of them to comply with state law. They now seek the ability to own them again.

A federal district court initially ruled against the two men and held that the Second Amendment does not protect butterfly knives. They appealed the ruling to the Ninth Circuit, which stayed the case pending the Supreme Court’s then-imminent ruling in New York State Rifle & Pistol Association v. Bruen last summer. The high court’s eventual ruling in Bruen last June laid out a new history-and-tradition test for weighing restrictions on the individual right to bear arms. In general, it required courts to determine whether there was a historical analogue for a challenged restriction and strike it down if none could be found.

“When the Second Amendment’s plain text covers an individual’s conduct, the Constitution presumptively protects that conduct,” Justice Clarence Thomas wrote for the court. “The government must then justify its regulation by demonstrating that it is consistent with the nation’s historical tradition of firearm regulation. Only then may a court conclude that the individual’s conduct falls outside the Second Amendment’s unqualified command.”

This test, as I’ve noted before, has had a dizzying array of outcomes in the lower courts. The Supreme Court is set to review one of those rulings this fall in United States v. Rahimi, where the justices will consider whether gun possession bans for people under certain types of domestic violence restraining orders violate the Second Amendment. A federal district court in Texas concluded that they were unconstitutional earlier this year, noting that early American lawmakers imposed no such restrictions in the founding era—a period when women generally had few legal or civil rights.

One notable limitation on the Bruen test, at least at first glance, is that it hitherto only applied to “firearms.” The Ninth Circuit panel, however, concluded that language was no impediment to the knife challenge. “Although Bruen discussed ‘firearm regulation[s],’ that was because the arm at issue in that case was a firearm,” Bea wrote. “We see no reason why the framework would vary by type of ‘arm.’” Those types of weapons, the court noted, can also be used for self-defense.

Hawaii pointed to another potential defense for its ban: District of Columbia v. Heller, the 2008 Supreme Court case that established an individual right to bear arms in the Second Amendment. In that decision, the high court suggested that some types of categorical weapon bans remained presumptively constitutional. The Heller justices specifically declined to overturn United States v. Miller, a 1939 case that upheld a federal law banning certain types of guns commonly associated with criminal activity, such as sawed-off shotguns and fully automatic rifles.

“We also recognize another important limitation on the right to keep and carry arms,” Justice Antonin Scalia explained in Heller.Miller said, as we have explained, that the sorts of weapons protected were those ‘in common use at the time.’ We think that limitation is fairly supported by the historical tradition of prohibiting the carrying of ‘dangerous and unusual weapons.’”

The panel, however, sidestepped Hawaii’s invocation of Heller. First, it denied a motion by the state to remand the case back to the lower court so it could build a factual record for the Bruen test, which did not exist when the district court upheld the law. Then the panel concluded that Hawaii should have already built that record when it defended the ban in the district court since Heller already existed at that point, even though the Bruen test did not. Accordingly, Bea wrote, the state had “failed to present evidence sufficient to create a genuine issue of material fact as to whether butterfly knives are dangerous and unusual.”

From there, the panel declared that there was “no genuine issue of material fact as to whether butterfly knives are commonly owned for lawful purposes.” It cited some testimony during the lower-court trial that butterfly knives can be used in self-defense and that the knives’ use is part of a martial arts style that originated in the Philippines. While Hawaii cited what the panel described as “some conclusory statements in the legislative history” that butterfly knives were associated with criminal activity, Bea wrote that the court gave “little weight” to those findings. “Common sense tells us that all portable arms are associated with criminals to some extent, and the cited conclusory statements simply provide no basis for concluding that these instruments are not commonly owned for lawful purposes,” he concluded.

Nor did the panel find any of Hawaii’s purported historical analogues to be convincing. The closest match, the judges said, was an 1837 Georgia law that declared no one shall “keep, or have about or on their person or elsewhere … Bowie, or any other kind of knives.” They reasoned that it was “not apparent to us that ‘other kind[s] of knives’ would have been understood to include pocketknives.” Nor did laws banning the possession and/or carry of more eclectic stabbing implements like Arkansas toothpicks, Bowie knives, daggers, dirks, or the like persuade them because, they concluded, a butterfly knife “is clearly more analogous to an ordinary pocketknife.”

Nor did the claimed emergence of novel societal problems that were unforeseen by the founding generation persuade the panel to uphold the law. In our August issue, I wrote about how Bruen was part of a growing trend where the Supreme Court and its rulings squelch policymaking innovation by lawmakers. If I wrote that article again today, I would undoubtedly include a portion of Monday’s ruling in Teter where the panel knocked down Hawaiian lawmakers’ rationale for the ban by dialing up the degree of specificity.

“Here, the 1999 Hawaii Legislature addressed the perceived social problem of an ‘increasing trend in minors and gang members armed with knives and daggers,’ who preferred butterfly knives ‘as they are easy to conceal and are more intimidating when brandished,’” Bea wrote. “But the problem of people using easily concealable, foldable knives in violent crimes predates 1999 by hundreds of years.”

While the court only addressed Hawaii’s butterfly knife ban, its interpretation of the Second Amendment and its application of the Bruen test could apply to a variety of other statutes. The panel concluded that bladed weapons fell within the scope of the Second Amendment by citing Malachy Postlethwayt’s Universal Dictionary of Trade and Commerce. Published in 1774, that dictionary defines “arms” to include “fascines, halberds, javelins, pikes, and swords,” according to the panel.

Under that framework, a wide variety of knife-related laws could conceivably be challenged. Hawaii’s own statutes have a similar ban on switchblade knives that could run afoul under this interpretation of the Second Amendment. California, which is also in the Ninth Circuit, bans the possession of an even wider assortment of bladed weapons, including dirks, daggers, ballistic knives, belt buckle knives, lipstick case knives, cane swords, and more. If the Second Amendment is not limited to firearms, Monday’s ruling also calls into question state-level bans on weapons like truncheons, saps, billy clubs, nunchucks, and the like.

The panel’s sidestepping of Heller and Miller’s restriction on “dangerous and unusual weapons,” coupled with its stark dismissal of legislative conclusions about what qualifies as one, could potentially affect some bans on specific types of firearms. Monday’s ruling does not directly affect restrictions on these types of guns; the decision itself is limited to Hawaii’s butterfly knife ban. But its narrower approach to deciding what counts as a “dangerous and unusual” weapon could call into question state-level bans on assault rifles and other type-specific restrictions. While the federal assault weapons ban expired in 2004, other federal laws still restrict the possession of fully automatic rifles manufactured after 1986.

All of this depends on whether the panel’s ruling stands on review. Like other federal appeals courts, the Ninth Circuit has a mechanism to review panel decisions through a super-panel of sorts, which includes a random assortment of its sitting judges. Democratic appointees on the Ninth Circuit have a narrow majority in its 29 seats at the moment, but the court’s sizable bloc of Republican appointees has frequently signaled an interest in aggressively enforcing the Bruen test on gun laws in its jurisdiction.

Either way, it seems likely that the Supreme Court will have to decide at some point what weapons count as “arms” under the Second Amendment, as well as which ones are “dangerous and unusual” in a post-Bruen world. In Rahimi, the upcoming domestic violence case, we’ll get a look at whether the justices want to clarify or refine the history-and-tradition test now that they’ve seen it in practice. How the court rules in that case will shape how it addresses Monday’s ruling in Teter and the rest of the Second Amendment’s yet-to-be-explored frontier.