HONOLULU, HI. – Everytown for Gun Safety Support Fund filed this amicus brief in the United States District Court for the District of Hawaii in a case challenging under the Second Amendment a Hawaii 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”). Everytown’s brief makes two doctrinal points in response to arguments advanced by plaintiffs. First, Everytown demonstrates that plaintiffs’ categorical “common use” test is inconsistent with binding court of appeals precedent, contrary to fundamental principles of federalism, and illogical. Second, the brief explains why, under controlling authority, the “strict scrutiny” standard argued for by plaintiffs is not the correct Second Amendment standard.