Gov. Gavin Newsom announced Friday he'll support Proposition 42, a ballot measure that would ban California from ever imposing wealth taxes, according to a report published by CalMatters on October 11, 2026. The endorsement puts him at odds with his own Democratic Party and aligns him with billionaire donors who've bankrolled the measure to defeat a separate proposal that would tax the ultra-wealthy. Newsom revealed his stance as part of a broader announcement covering most of the 14 propositions facing voters this November.
Proposition 42 would block retroactive taxes, including the one-time 5% levy on assets that would hit any billionaire living in California on Jan. 1, 2026 if Proposition 40 passes. But the measure goes much further, prohibiting any future taxes on personal property including pensions and 401K accounts before retirees withdraw income, along with investments, financial holdings, business stakes, art collections, and all other forms of personal wealth. Google co-founder Sergey Brin funded and placed Prop. 42 on the ballot specifically to nullify Prop. 40, the billionaire tax backed by a healthcare union that would direct 90% of revenues toward Medi-Cal, the state's low-income health program. Newsom hasn't yet announced a position on Proposition 41, another Brin-backed anti-tax measure that would subject billionaire tax revenues to spending caps and audits, according to his spokesperson.
"We all agree that Californians deserve to have their retirement and life savings protected from new state taxes," Newsom said in a statement released by Prop. 42 supporters, which include police and fire unions. Service Employees International Union vice president Debru Carthan criticized the endorsement as evidence the governor is "in lock step with his billionaire backers," stating he'd rather see millions lose healthcare than ask hundreds of billionaires to pay their share. CalMatters reports that Newsom has opposed state-level asset taxes throughout his two terms as governor, worried that wealthy residents will relocate and take their income tax payments with them. The California Democratic Party endorsed the billionaire tax, and polling indicates a slim majority of likely voters back it.
The report notes that Newsom has tried to navigate competing political pressures this year as he weighs a potential presidential run after leaving office. He announced a proposal over the summer for a national wealth tax targeting anyone worth more than $100 million, along with plans to reverse 2017 corporate tax cuts, increase inheritance taxes, and close loopholes that let the wealthy borrow against unrealized capital gains without paying income taxes. Democratic Rep. Ro Khanna, another possible 2028 presidential candidate, called donor relationships "the only reason" for Newsom's opposition to Prop. 40 while campaigning for the billionaire tax last weekend. Khanna pointed to Brin, who attended Newsom's wedding and has never donated to him but maintains a years-long relationship with the governor and recently shifted rightward to court Trump's favor.
Newsom also announced positions on most other November ballot measures, endorsing the majority but opposing Proposition 39, the Republican-backed voter ID requirement; Proposition 43, which would make passing local taxes harder; and Proposition 44, a health union measure mandating spending levels at clinics serving low-income patients. He hasn't taken a stance on Proposition 45, the business-backed measure imposing time limits on environmental reviews for new developments. The governor's willingness to break with his party on the wealth tax question underscores the tension between California Democrats' populist messaging and Newsom's longstanding ties to Silicon Valley donors dating back to his tenure as San Francisco mayor.