Whether the grant of concurrent jurisdiction divests federal courts of enclave jurisdiction

QUESTIONS PRESENTED For decades, the Circuit Courts have interpreted the Enclave Clause of the United States Constitution to provide federal courts with jurisdiction over civil actions that arise on military bases and other federal enclaves. Here, the district court found that the Enclave Clause permitted the removal of a series of cases alleging that military housing on Marine Corps Base Hawaii was unsafe. The cases challenged the viability of the base’s housing program; raised issues related to the federal Military Housing Privatization Initiative; and implicated numerous Navy interests. On appeal, the Ninth Circuit broke with its precedent and that of at least two other circuits when it held that the district court lacked enclave jurisdiction because the United States had granted Hawaii concurrent jurisdiction under the Hawaii Admission Act. The Ninth Circuit further held that the case only implicated federal “policy,” not federal “law.” The questions presented by this Petition are: 1. Where the United States expressly reserves jurisdiction over a federal enclave, but permits a state to exercise concurrent jurisdiction, does such grant of concurrent jurisdiction divest the federal courts of the jurisdiction that they would otherwise have under the Enclave Clause? 2. Alternatively, does federal question jurisdiction require that a “‘right or immunity created by the Constitution or laws of the United States must be an element, and an essential one, of the plaintiff’s cause of action,’” or is it sufficient that the case implicates substantial federal issues?