The Navahine settlement is a court-approved agreement, signed off by Hawaiʻi State Environmental Court Judge John Tonaki on June 20, 2024, that requires the Hawaiʻi Department of Transportation to eliminate greenhouse gas emissions from ground transportation, interisland sea transport, and interisland air travel by 2045.1Earthjustice. Historic Agreement Settles Hawaiʻi Youth-Led Constitutional Climate Complaint It resolved a constitutional lawsuit brought by thirteen young Hawaiʻi residents and is the first settlement of its kind against a government transportation agency anywhere in the world.
How the Case Reached a Settlement
Thirteen youth plaintiffs filed Navahine F. v. Hawaiʻi Department of Transportation on June 1, 2022, in Honolulu Circuit Court. They were represented by Our Children’s Trust and Earthjustice.2Our Children’s Trust. Navahine F. v. Hawaiʻi Department of Transportation Their argument rested on the Hawaiʻi Constitution: that HDOT’s operation of the state transportation system produced greenhouse gas emissions at levels that violated their right to a clean and healthful environment under the state’s public trust doctrine.3Sabin Center for Climate Change Law. Navahine F. v. Hawaiʻi Department of Transportation
In April 2023, the court denied the state’s motion to dismiss, rejecting arguments about standing and the political question doctrine.3Sabin Center for Climate Change Law. Navahine F. v. Hawaiʻi Department of Transportation Trial was set for late June 2024. It never happened. On June 20, 2024, with the trial scheduled to begin the following Monday, Judge Tonaki approved a settlement announced at a joint press conference with Governor Josh Green, HDOT Director Edwin Sniffen, and the youth plaintiffs.2Our Children’s Trust. Navahine F. v. Hawaiʻi Department of Transportation
What HDOT Agreed to Do
The core promise is a hard deadline. HDOT must achieve zero emissions for all ground transportation, interisland sea transport, and interisland air travel by 2045.1Earthjustice. Historic Agreement Settles Hawaiʻi Youth-Led Constitutional Climate Complaint Around that deadline, the agreement layers in specific obligations:
- Prepare a concrete and comprehensive statewide greenhouse gas reduction plan by May 2025, including interim targets for 2030, 2035, and 2040.3Sabin Center for Climate Change Law. Navahine F. v. Hawaiʻi Department of Transportation
- Use an objective, science-based methodology to assess the long-term greenhouse gas and vehicle-miles-traveled impacts of every infrastructure project.4Environmental Law Institute. Landmark Climate Settlement Highlights Relevance of Climate Science for Judges
- Create a dedicated climate change mitigation unit led by a Climate Change Mitigation and Culture Manager, and establish a volunteer youth advisory council.4Environmental Law Institute. Landmark Climate Settlement Highlights Relevance of Climate Science for Judges
- Complete pedestrian, bicycle, and transit networks within five years and invest at least $40 million to expand the public electric vehicle charging network by 2030.1Earthjustice. Historic Agreement Settles Hawaiʻi Youth-Led Constitutional Climate Complaint
- Overhaul how transportation projects are evaluated and prioritized to favor reductions in emissions and vehicle miles traveled, with transparent disclosure of each project’s climate impact.1Earthjustice. Historic Agreement Settles Hawaiʻi Youth-Led Constitutional Climate Complaint
The agreement also formally recognizes the state’s duty to protect public trust resources and citizens’ right to a clean environment. It acknowledges the scientific consensus that atmospheric carbon dioxide must fall below 350 parts per million this century to stabilize the climate.4Environmental Law Institute. Landmark Climate Settlement Highlights Relevance of Climate Science for Judges
Enforcement is built in. The Hawaiʻi Circuit Court retains jurisdiction over the settlement until either December 31, 2045, or the date the zero-emissions target is met, whichever comes first.3Sabin Center for Climate Change Law. Navahine F. v. Hawaiʻi Department of Transportation That means the plaintiffs, and the court, can hold HDOT to the schedule for the next two decades.
One boundary worth noting: the settlement binds the Hawaiʻi Department of Transportation. It does not by its own terms reach the state’s electricity sector, its private aviation carriers, or interstate air travel, and it does not create direct obligations for other state agencies. The reductions it commands are those within HDOT’s transportation footprint.
Where Implementation Stands
HDOT released a draft of its statewide emissions reduction plan on June 27, 2025, slightly past the May deadline. The document, titled the Hawaiʻi Energy Security and Waste Reduction Plan, was described by plaintiffs’ counsel as a “major milestone.”5Earthjustice. State Plan to Reduce Transportation Emissions Released for Public Comment The plan sets out strategies across three sectors: electrification of light, medium, and heavy-duty vehicles; expansion of public transit, bike lanes, and pedestrian infrastructure; and exploration of sustainable fuel alternatives for marine and long-haul air travel.6WBUR. Hawaiʻi Zero Emissions Plan
The organizational changes required by the settlement have also moved forward. HDOT formed a new leadership team headed by Laura Ka’akua, developed a calculator tool to prioritize projects that reduce vehicle miles traveled, and launched its Inaugural Youth Transportation Council.5Earthjustice. State Plan to Reduce Transportation Emissions Released for Public Comment Andrea Rodgers, counsel for the plaintiffs, called the draft plan a “work in progress” and “an all-of-the-above menu of options” open to public feedback.6WBUR. Hawaiʻi Zero Emissions Plan What comes next is a public comment process on the draft, followed by finalization and the interim 2030 target that the plan is meant to anchor.
Why the Settlement Drew So Much Attention
Navahine landed as the concrete win that a decade of youth climate litigation had been chasing. The federal case that started the movement, Juliana v. United States, was effectively ended when the U.S. Supreme Court denied certiorari on March 24, 2025, closing a decade of litigation without a trial on the merits.7U.S. Department of Justice. Justice Department Statement on Juliana Case The Ninth Circuit had twice instructed the district court to dismiss for lack of Article III standing.8Inside Climate News. Supreme Court Declines to Hear Juliana v. United States Where Juliana never reached trial, Navahine produced binding, court-supervised obligations.
It was not alone. In August 2023, a Montana district court ruled in Held v. State of Montana that a state law barring environmental regulators from considering greenhouse gas emissions violated the Montana Constitution’s guarantee of a clean and healthful environment. The Montana Supreme Court affirmed on December 18, 2024, holding that the constitutional right includes the right to a “stable climate system that sustains human lives and liberties.”9Justia. R. Held v. State, 2024 MT 312 Our Children’s Trust, the same organization behind Juliana and Navahine, has said the Juliana legal framework inspired more than 60 youth-led climate lawsuits worldwide.8Inside Climate News. Supreme Court Declines to Hear Juliana v. United States
What sets the Navahine settlement apart is its specificity. Rather than a court declaration that a right exists, it commits a state agency to dated targets, dollar amounts, staffing decisions, and a science-based project review method, and it keeps a judge watching until 2045.