Washington Supreme Court strikes down voter-approved natural gas initiative, setting new precedent

After almost 2 million Washingtonians voted to preserve access to natural gas, the Washington Supreme Court has thrown out Initiative-2066.

In a 6-3 decision Thursday, the court ruled that I-2066 violated the Washington Constitution’s single-subject requirement. The majority concluded that several provisions of the initiative represented distinct subjects and could not be separated from the rest of the measure, requiring the entire initiative to be invalidated.

Washington voters approved I-2066 by 51.7% in November 2024, with 1,941,474 voting yes. The initiative was put on the ballot after more than half a million signatures were submitted to the Secretary of State.

The measure was a response to HB 1589, which was signed into law by former Gov. Jay Inslee in 2024. It allows Puget Sound Energy (PSE) to shut down natural gas service for its customers – effectively making the bill a ban on natural gas. It includes no support for families to make an all-electric transition that could cost tens of thousands of dollars and could lead to energy bill increases of more than $200 each month.

The Building Industry Association of Washington, which sponsored I-2066, said Thursday’s ruling disregards the preference expressed by nearly two million voters and again raises concerns about the affordability and reliability of forcing homes and businesses away from natural gas.

In a statement, Citizen Action Defense Fund (CADF), which was not directly involved in the lawsuit involving the natural gas ban but did file a lawsuit a couple of years ago challenging multi-subjects in a legislative bill, said, “The courts in our state that are applying [the single-subject] constitutional provision are using different standards for measures passed by the people as opposed to those passed by the Legislature. Why does this matter? Because it creates a legally dangerous situation: courts are effectively giving themselves the ability to tip the scales of justice based on political considerations.”

The Washington Hospitality Association raised similar concerns, noting that restaurants and hotels still face the potentially significant cost and practical difficulty of converting commercial kitchens and building systems away from gas.

But the consequences of the ruling may extend well beyond natural gas.

The state Constitution’s single-subject restriction does not apply only to citizen initiatives. The Supreme Court expressly recognized that the legislature is also subject to the same constitutional restraints when it passes laws.

In Thursday’s ruling, the court emphasized that individual provisions must have “rational unity” not only with the legislation’s general subject, but also with one another. The majority also clarified that even broadly written omnibus legislation must satisfy that standard, although comprehensive legislation addressing one overall problem may still qualify.

That creates an important question for the legislature.

BIAW argues that the standard used to strike down I-2066 must now be applied consistently to legislation passed by lawmakers and that the decision puts “many” existing state laws in legal doubt.

In practical terms, potentially dozens of broad laws passed by the Legislature could now be examined for the same kind of single-subject problem, particularly laws combining provisions with substantially different regulatory effects. Whether any particular law would actually be struck down remains an open question, but Thursday’s decision gives future challengers a new Supreme Court precedent to cite.

There are no further appeal options for I-2066.

But the constitutional standard the Supreme Court used to ban natural gas will now apply the next time someone challenges legislation.