On June 20, 2024, four days before the case was set to go to trial, Hawaiʻi’s First Circuit Court approved a landmark settlement that resolved claims brought by thirteen Hawaiʻian youth plaintiffs against Hawaiʻi’s Department of Transportation (HDOT) and other defendants, including the department director and Governor. That case, Navahine F. v. Hawaiʻi Department of Transportation (HDOT), filed on June 1, 2022, is the world’s first youth-led constitutional climate case that sought to hold the transportation sector accountable for climate pollution, and the first settlement between plaintiffs and a state government to address climate impacts. It is one in a wave of cases that seek to hold governments accountable for climate impacts under various constitutional rights.
A Last-Minute Settlement in a Landmark Case
Many of the Navahine plaintiffs are Native Hawaiʻians who alleged their health and well-being are being negatively affected by climate change and its impacts. The plaintiffs argued that Hawaiʻi was violating the state constitution by operating a transportation system that depends on fossil fuels that are harmful to Hawaiʻi’s climate system and that state officials breached their duties to “preserve, protect, and maintain public trust resources for present and future generations” by not acting quickly enough to transition away from fossil fuels.
In particular, the plaintiffs sought a declaration that the defendants’ actions violated their right under the Hawaiʻi state constitution that guarantees the right to a clean and healthful environment and provides that the state holds natural resources in trust “for the benefit of present and future generations.” They also sought injunctive relief, asking the court to compel the state to cease establishing, maintaining, and operating the transportation system in a way that violates HDOT’s constitutional obligations and to order HDOT to take concrete action to change the transportation system – changes they wanted overseen by someone appointed by the court.
HDOT sought to have the case dismissed, but in April 2023, that request was denied, putting the case on the path for trial. Just before the trial was set to start, the parties announced a court-approved settlement that outlines HDOT’s various commitments to decarbonize Hawaiʻi’s transportation system.
The centerpiece of the settlement is the requirement for HDOT to develop a “Greenhouse Gas (GHG) Reduction Plan.” By May 2025, the state must submit a comprehensive statewide plan that outlines the actions and investments needed to decarbonize Hawaiʻi’s transportation infrastructure. The plan will set interim 5-year GHG emission reduction targets, through 2045. To get there, HDOT must “take any actions necessary” to achieve the goals established in the settlement; specifically, zero GHG emissions across all ground transportation as well as any sea and air interisland transportation within Hawaiʻi by 2045.
To assist with plan implementation, HDOT agreed to create a lead unit, headed by a Climate Change Mitigation and Culture Manager, who is charged with addressing climate change mitigation and ensuring the interim GHG emission reduction targets are met. Other commitments in the settlement include accelerating the expansion of electric vehicle charging networks, promoting different modes of transportation, and increasing efforts to sequester carbon. To ensure compliance with the settlement terms over time, the court will maintain continuing jurisdiction through 2045, or until the Zero Emissions Target is reached.
The Navahine settlement also emphasizes collaboration between HDOT, plaintiffs, and the public. For example, plaintiffs and the public will have the chance to provide feedback and comments before the plan is finalized. And HDOT is required to provide annual progress updates on implementing the GHG Reduction Plan, with notice specifically provided to the plaintiffs. The settlement includes a mechanism for plaintiffs and the public to provide feedback on the annual updates too.
The Science of It All
Climate science was featured prominently in court filings throughout the lawsuit – and the settlement requires science-based decision making. The settlement itself states that Hawaiʻi’s courts recognize the existence of a scientific consensus that anthropogenic global warming "threatens the world's climate system." This is important because it sets a clear context for future processes, ensuring that future legal frameworks recognize established science and are informed by current scientific understanding.
Similarly, the settlement reiterates positions of the state legislature, including statements that the state is particularly vulnerable to the dangers of weather and climate-related disasters. And that “the best scientific evidence available today shows that correcting Earth’s energy imbalance requires reducing atmospheric carbon dioxide to less than 350 parts per million this century.” In other words, that best science calls for rapid decarbonization. Other relevant climate science acknowledged in the settlement, was a 2023 U.S. EPA study that found that children are uniquely vulnerable to climate impacts due to their developing physiologies. These acknowledgements could have far-reaching implications by providing a basis for developing science-based climate policies and guiding actions to address climate issues.
Climate science is also central to determining whether or not the state is meeting its emissions reductions goals. Specifically, the agreement requires “an objective, scientifically based methodology to assess and report the total, long-term [greenhouse gas] emission and [vehicle miles traveled] impacts of each infrastructure project.”
The reliance on “best available science” in the acknowledgements of the legislature raises questions, particularly regarding how the “best available science” is determined and how it will specifically be used. However, the use of climate science to design effective benchmarks, mitigation strategies, and goals will be essential in the implementation of the GHG reduction plan and in the establishment of the lead unit to coordinate Hawaiʻi’s transportation decarbonization efforts by 2045.
While the settlement is a significant development in climate litigation, its implementation and enforcement remain to be seen, especially for loftier goals in the settlement like decarbonizing air travel, where there are currently no feasible ways to power commercial jets and ships without fossil fuels. However, if the enthusiasm of all parties towards a collaborative future is any indication, this combined effort will mark a pivotal step in Hawaiʻi’s efforts towards the decarbonization of its transportation sector by 2045. In reflecting on the recent developments, Hawaiʻi’s Governor Josh Green offered an insightful perspective: “This settlement informs how we as a state can best move forward to achieve life-sustaining goals and further, we can surely expect to see these and other youth in Hawaiʻi continue to step up to build the type of future they desire.”
This blog post was originally posted on ELI's Vibrant Environment blog: https://www.eli.org/vibrant-environment-blog/landmark-climate-settlement-highlights-relevance-climate-science-judges
