Washington Supreme Court Blocks Referendum Challenge to Millionaires Income Tax
Why It Matters
The Washington Supreme Court’s decision to reject a conservative group’s referendum challenge to the state’s new millionaires’ income tax has significant implications for taxpayers across the Pacific Northwest. The ruling effectively removes a faster, lower-threshold path for voters to reject the tax, leaving opponents to pursue a more difficult initiative process requiring twice as many signatures.
The decision also raises broader questions about legislative tactics and the extent to which Democratic-controlled legislatures can shield tax increases from direct voter review — a concern that resonates beyond Washington’s borders in neighboring Idaho and other Mountain West states.
What Happened
The Washington state Supreme Court on Monday denied a request from conservative political committee Let’s Go Washington to pursue a referendum this fall against the state’s newly enacted income tax on high earners. Chief Justice Debra Stephens signed the ruling, holding that the law’s so-called “necessity clause” — which shields it from referendum — is constitutionally valid.
Gov. Bob Ferguson signed the legislation, Senate Bill 6346, into law on March 30. The law imposes a 9.9% levy on household wage income exceeding $1 million, with collections set to begin in 2029.
Secretary of State Steve Hobbs had initially rejected the referendum filing, citing a provision embedded in the 109-page bill that expressly prohibits such a vote. The provision states the tax “is necessary for the support of the state government and its existing public institutions.” Brian Heywood, founder of Let’s Go Washington and the measure’s primary financial backer, filed an emergency petition asking the justices to overturn Hobbs’ decision.
The court sided with the state, ruling the necessity clause is consistent with the state constitution and an “unbroken line of precedent,” as Stephens wrote in the decision. The court did not release a vote tally among the justices.
By the Numbers
- 9.9% — levy rate on household wage income above $1 million under the new law
- 154,455 — signatures required by June 10 to qualify a referendum for the fall ballot (the path now blocked)
- 308,911 — signatures required by July 2 to qualify an initiative for the ballot this year
- 2029 — earliest year tax collections would begin under the law
- April 9 — date the Citizen Action Defense Fund filed a separate lawsuit challenging the tax’s constitutionality
Controversy Over Legislative Strategy
The ruling came amid a separate controversy involving communications between Democratic lawmakers and state attorneys. Public records released by the attorney general’s office included a December 2025 email from Solicitor General Noah Purcell to Senate Majority Leader Jamie Pedersen — one of the bill’s prime sponsors — warning that without a necessity or emergency clause, the bill could be subject to a referendum challenge.
Heywood’s attorney, Joel Ard, submitted that email as evidence that Democratic lawmakers intentionally included the necessity clause to block voters from challenging the tax via referendum. Pedersen disputed that characterization Monday, saying the clause was added to accelerate any legal resolution, not to circumvent voters.
Heywood was pointed in his criticism of the ruling. “This ruling states that the people cannot challenge via referendum any tax imposed by the legislature, removing any guardrails from the people on runaway spending,” he said in a statement. He argued the decision gives Democratic leaders “a blank check to spend beyond their means and raise taxes later, and the people don’t get to weigh in.”
House Majority Leader Joe Fitzgibbon, D-Seattle, called the ruling “good news” for the session’s tax reform efforts, saying the outcome was not unexpected. This reflects a growing pattern of courts weighing in on electoral and legislative boundary disputes with far-reaching consequences for voters’ direct input into government decisions.
What’s Next
Monday’s ruling is not the Washington Supreme Court’s final word on the income tax. The court will still need to rule on the law’s constitutionality before the state can begin collecting revenue under it. The Citizen Action Defense Fund’s lawsuit, led by former state Attorney General Rob McKenna and former state Supreme Court Justice Phil Talmadge, challenges whether the tax is constitutional under Washington law.
In the meantime, Let’s Go Washington can still pursue an initiative — either submitting approximately 309,000 signatures by July 2 for a fall 2026 ballot measure, or by December 31 to send the question to the Legislature. That path, while still open, requires significantly more resources and organizing than the referendum route the court shut down Monday.
About the Author
