Nearly 70% of Tax Scholars Would Vote Against California's Billionaire Tax

Nearly 70% of tax academics would vote against California's proposed billionaire tax, according to a new survey of 105 members of the National Tax Association. Jeff Hoopes, a professor at the University of North Carolina and research director of the UNC Tax Center, polled the professional group of mostly academic economists, accountants, and lawyers. Of the 105 respondents, 73 (69.5%) said they would vote against Proposition 40, and 32 (30.5%) said they would vote for it.

Prop 40 would impose a one-time 5% tax on the wealth of California's roughly 250 billionaires. Headlines have tracked billionaires fleeing the state over the proposal. The survey asks a different question: what do the people who study taxes for a living think? The answer cuts against the measure.

Which scholars oppose it — and which don't?

Accountants were the most opposed. Seventeen of 20, or 85%, rejected the tax. Among economists, 49 of 69 (71%) opposed it. Lawyers broke the other way: nine of 15 (60%) favored the measure.

Law professors also wrote much of it. Three of its principal drafters — Brian Galle, David Gamage, and Darien Shanske — are tax-law professors. That split between lawyers and everyone else is the survey's clearest pattern.

Opposition does not equal hostility to wealth taxation itself. "The 70% of folks who would not vote for Prop 40 seems to have two different camps," Hoopes told Fortune. "Those who would favor wealth taxes in general, but just thought this particular version was bad, and those who don't think a wealth tax is a good idea at all."

Why did scholars vote no?

Respondents explained their votes in written comments. Those in Hoopes' first camp said they would back a federal wealth tax but doubted a single state could enforce one when billionaires and their assets can move. Others questioned whether a "one-time" tax would stay that way. Some warned that valuing private companies would trigger costly disputes.

Supporters in the sample cited the efficiency of a surprise tax on wealth already built up, the case for reducing concentrated wealth, and the revenue it would raise.

For Hoopes, the main risk is migration. "I think there is a real chance that we see some billionaires change where they claim residency based on this tax," he said. Norway offers a precedent, he noted: its very richest moved in response to its wealth tax. "It would not take very many of the very richest ones moving to make a large dent in the expected tax revenue."

He pointed to Elon Musk, who moved from California to Texas and cited taxes as part of the reason. "It's not crazy to think this might push other like-minded billionaires over the edge," Hoopes said, noting California already has the highest top income tax rate in the country.

His spending critique was blunt. "In a state that is near the very top in both spending and taxes per capita, it's clear California has a spending problem," he said. "If I had a friend who made $600,000 a year but had $700,000 in expenses, I would not tell him to get some side-hustle to bring in extra money. I would say figure out how to live on the extraordinary income he already has."

What does it mean for revenue estimates?

The tax could raise as much revenue as a 5% income tax on all Californian taxpayers, and supporters say it could bring in about $100 billion to backfill federal Medicaid cuts. The drafters' own estimate supports that figure. A Hoover Institution working paper throws water on it, projecting the state could lose more in future income tax revenue than the wealth tax collects.

What prompted the survey — and what are its limits?

Hoopes ran the poll after six Nobel Prize–winning economists, including Paul Krugman and Joseph Stiglitz, endorsed the measure in September. "I was baffled, because even the left-leaning economists I know were against it," he said. "It turns out the economists I know personally are much more like the 105 people who responded to my survey than the six people who won a Nobel Prize."

The survey has limits. Hoopes used a 2024 membership directory. The NTA did not sponsor or approve the poll, and Hoopes sits on the advisory council of the right-leaning Tax Foundation.

Voters themselves are more evenly split. A September Public Policy Institute of California poll found 52% of likely voters back Prop 40. But the same poll showed majorities also supporting Props 41 and 42 — two measures funded largely by Google cofounder Sergey Brin that would effectively cancel the tax. The scholarly skepticism may prove more predictive than the endorsements, or less; the ballot decides in November.