Charting the Boundaries of Hawaii's Extensive Public Trust Doctrine Post-Waiāhole Ditch

Abstract

Hawaii’s public trust doctrine is unique in its breadth, its origins, and its constitutional basis. Perhaps the most expansive in the United States, the Hawaii public trust doctrine extends to water, land, air, minerals, natural beauty, and Native Hawaiian cultural practices. Although the majority of Hawaii’s public trust cases concern water issues, the Hawaii Supreme Court has also applied the public trust doctrine in several important land cases. Significantly, the court has applied the doctrine to land extensions created during volcanic eruptions and, most recently, to Mauna Kea, a mountain peak controversially used for both modern astronomy and Native Hawaiian cultural practices. I survey several public trust cases, beginning with Waiāhole Ditch—a water case widely regarded as the cornerstone of Hawaii’s modern public trust doctrine—and ending with the Hawaii Supreme Court’s 2018 decision in Mauna Kea II. A survey of the case law reveals that the expansive nature of Hawaii’s public trust doctrine has not always led to greater protections for all trust resources, as courts have ruled that the doctrine requires a balancing between protection and maximum beneficial use. Applying this balancing test, court opinions have, in some cases, resulted in greater protection for Native Hawaiian rights to trust resources. In other cases, however, court application of the balancing test has resulted in resource allocations that harm native interests. In light of the dichotomous results, this paper recommends that Hawaii agencies like the Department of Land and Natural Resources develop inclusive participatory processes ensuring that Native Hawaiian concerns are fully ventilated before taking action affecting trust resources.