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Teter v. Lopez


Defending Hawai‘i’s prohibition on butterfly knives.

Courts: District of Hawaii; Ninth Circuit

Issue at Stake: Butterfly knives

Summary: Teter v. Lopez is a case challenging under the Second Amendment a Hawai‘i law prohibiting the possession of butterfly knives (which are defined by law as “kni[ves] having a blade encased in a split handle that manually unfolds with a hand or wrist action with the assistance of inertia, gravity, or both”). The United States District Court for the District of Hawaii upheld the law, rejecting plaintiffs’ Second Amendment challenge and granting summary judgment to the Hawai‘i Attorney General. Plaintiffs appealed the district court’s decision to the United States Court of Appeals for the Ninth Circuit.

On October 27, 2020, Everytown filed an amicus brief in the Ninth Circuit, urging the court to affirm the district court’s decision. The amicus brief raised three points in response to arguments advanced by plaintiffs. First, Everytown demonstrated that plaintiffs’ argument that Hawai‘i’s butterfly-knife law is “categorically unconstitutional” is contrary to binding Ninth Circuit precedent, inconsistent with the Supreme Court’s decision in District of Columbia v. Heller, illogical, and unworkable. Second, the brief explained why, under controlling authority, the strict scrutiny test argued for by plaintiffs is not the correct Second Amendment standard. Intermediate scrutiny is instead appropriate, and Hawai‘i’s law easily satisfies it. Third, Everytown set forth the long history of state laws prohibiting types of knives and other non-firearm weapons, which further supports the constitutionality of Hawai‘i’s prohibition on butterfly knives. Everytown filed a similar brief in the district court on January 23, 2020.

On September 27, 2022, Everytown filed an additional amicus submission arguing that Hawai‘i’s butterfly-knife law is constitutional under the approach to Second Amendment cases set out in New York State Rifle & Pistol Ass’n v. Bruen. The brief explained that plaintiffs failed to meet their burden under Bruen to establish that butterfly knives are protected “arms” within the meaning of the Second Amendment. The brief further argued that historical analysis should center on 1868, not 1791. Finally, the brief showed that the long history of regulations set out by the State demonstrates the constitutionality of Hawai‘i’s law, and that plaintiffs’ arguments about the number of laws a government must produce to establish a historical tradition are inconsistent with Bruen.

After a panel of the Ninth Circuit ruled for the plaintiffs, Hawai‘i filed a petition for rehearing en banc. Everytown, along with other gun-violence-prevention groups and policy researchers, filed an amicus brief in the Ninth Circuit supporting Hawai‘i’s petition for rehearing. The brief explained that the panel decision misapplied the approach to Second Amendment cases set out in New York Rifle & Pistol Ass’n v. Bruen, relied on unfounded factual assumptions, and, if allowed to stand, could be used to upend gun-safety regulations throughout the country. 

Decision: On May 13, 2020, the district court issued a ruling rejecting plaintiffs’ arguments and upholding Hawai‘i’s butterfly-knife law. The district court’s decision expressly cited and relied on Everytown’s amicus brief. The plaintiffs appealed. On August 7, 2023, a panel of the Ninth Circuit reversed the district court’s decision and ruled that Hawai‘i’s law violates the Second Amendment. On February 22, 2024, the Ninth Circuit granted rehearing en banc and vacated the panel opinion.

Case Documents