Actor Mark Ruffalo has sharply criticized California Gov. Gavin Newsom over his opposition to a proposed California billionaire tax, accusing the Democrat of siding with wealthy interests over working families and questioning his suitability for higher office. The clash comes weeks before California residents head to the polls to vote on Proposition 40, a ballot initiative that would impose a one-time tax equal to 5% of net worth on billionaires who were California residents on Jan. 1, 2026, if approved.
“It’s beyond sad,” Ruffalo posted on X. “It’s beyond disappointing; at this point, it’s disqualifying for anyone with ambitions for higher office as a Democrat, or a Republican, for that matter, to be fighting to keep billionaires from being taxed while kids don’t have health insurance and the cost of living goes sky-high.”
Ruffalo made the remarks Friday while reposting criticism from Rep. Ro Khanna, D-Calif. — a supporter of the California billionaire tax — who objected to Newsom’s support for Proposition 42, a separate measure on the Nov. 3 ballot.
The California Billionaire Tax Fight: Prop 40 vs. Prop 42
The California billionaire tax debate centers on two competing November ballot measures. Proposition 40, endorsed by the California Democratic Party, would levy the one-time 5% wealth tax on billionaires. The tax would be due in 2027, although payments could be spread over five years at an additional cost. Real estate, pensions and retirement accounts would generally be excluded from the tax.
Proposition 42, backed by Newsom, would prohibit California from establishing new state taxes on the ownership of financial assets and other personal property, as well as certain retroactive taxes. If approved, it could prevent Proposition 40 from taking effect — effectively blocking the California billionaire tax before it ever applies.
Newsom has been outspoken against Prop 40 since January. “We all agree that Californians deserve to have their retirement and life savings protected from new state taxes so those savings are there when they need them,” he said in a prior statement. While the measure has been endorsed by the state Democratic Party, some prominent Democrats, including Newsom, have opposed it.
California Billionaire Tax Vote Looms on Nov. 3
Ruffalo’s criticism is part of a sustained campaign. Earlier this month, the actor — known for roles in The Avengers and the upcoming Avengers: Doomsday — called Newsom out for endorsing Prop 42, writing on X: “Just like the Paramount merger, Gavin Newsom does what he always does: Sells out the working class people for the billionaires again and again. Not only that but endorses a bill that will make it impossible to tax the wealthy at all.”
Khanna had called Newsom a “poster child” for banning new wealth taxes on billionaires, sharing an image of a Newsom-backed advertisement urging Californians to vote “yes” on Proposition 42. Ruffalo’s repost amplified the congressman’s message to his millions of followers.
Opponents of the California billionaire tax warn it could drive wealthy residents and businesses out of the state, with one California entrepreneur warning of a “giant sucking sound” of business exits. Supporters argue the state needs new revenue as the cost of living climbs and services strain.
Both campaigns are expected to pour tens of millions of dollars into the fight, with business groups lining up against the measure and labor and progressive organizations backing it. Newsom, widely seen as a potential 2028 presidential contender, has framed his opposition as a matter of protecting retirement savings, while Ruffalo and Khanna have framed support as a question of fairness for working families caught in the state’s affordability crisis. Whatever the outcome on Nov. 3, the California billionaire tax debate has already become a national litmus test for how Democrats talk about taxing extreme wealth.
The November vote will settle whether California takes the unprecedented step of taxing billionaire wealth directly — or whether Newsom’s countermeasure shuts the door. With a major Hollywood star now framing the choice as a character test for any politician with national ambitions, the California billionaire tax fight is poised to echo well beyond the state’s borders.