Washington's highest court has struck down Initiative 2066, the voter-approved measure meant to protect access to natural gas, ruling that it violated the state Constitution by bundling multiple unrelated subjects into a single ballot question. The Washington Supreme Court's 6-3 decision found the initiative unconstitutional in its entirety, delivering a final blow to a measure that had already been thrown out once by a lower court.
The court's majority determined that I-2066 combined four distinct subjects that had no business being packaged into one initiative: natural gas access and supply, restrictions on air quality authority, changes to building codes, and amendments to the Washington Decarbonization Act for Large Combination Utilities, according to Courthouse News Service. Chief Justice Debra Stephens, writing for the majority, was blunt about the outcome, stating that “I-2066 is unconstitutional in its entirety” because its separate provisions could not be legally separated from one another.
The ruling caps a legal fight that began almost as soon as voters weighed in. Washington voters approved Initiative 2066 in 2024, though outlets differ slightly on the exact margin — Courthouse News reported a 51.7% majority, while the Washington State Standard and the Tri-City Herald put the figure at nearly 52% and 52%, respectively. The Washington State Standard also reported the measure passed in 34 of the state's 39 counties.
A Measure Meant To Keep the Gas Flowing
I-2066 was designed to explicitly protect access to natural gas in Washington and to weaken building codes that had made natural-gas heating more difficult and costly in new construction, per the Tri-City Herald. The measure filled 21 pages and contained more than a dozen sections touching on energy codes, natural-gas access, utility rate plans and the state's zero-emission goals, according to the Washington State Standard's reporting.
The initiative also touched on clean-air regulations and targeted legislation intended to help Puget Sound Energy transition away from natural gas, the Tri-City Herald reported. That breadth of subject matter ultimately became the measure's undoing — the same sprawling scope that supporters saw as a comprehensive defense of gas access is what the court's majority identified as unconstitutional logrolling.
This was not I-2066's first defeat in court. A King County Superior Court judge had already struck down the law in March 2025, per the Washington State Standard, months before the state Supreme Court took up the case and delivered its own, more sweeping conclusion that the entire measure could not stand.
Climate Groups Cheer, Backers Push Back
Environmental groups are celebrating the decision, according to FOX 13 Seattle. Climate Solutions said the ruling restores certainty to energy-efficiency and building-decarbonization efforts in Washington that had been left in limbo since the initiative passed, as reported by Courthouse News. Christina Wong, with Washington Conservation Action, is joining FOX 13 Seattle's Washington News Wrap program to explain what the decision means for the state's broader climate work.
Supporters of the initiative, meanwhile, have framed the ruling as a rejection of the voters who approved it in 2024. The measure's defenders argue the decision undercuts the initiative process itself, even as the court's majority maintained that the constitutional single-subject rule left no room to preserve any part of I-2066 once its provisions were found impossible to sever from one another.
