California's Proposition 40: Interview With the Architect of the World's First Billionaire Tax

Reuters Econ World examines Proposition 40, a California ballot measure that would impose a one-time 5% tax on the state's roughly 250 billionaires to help refill healthcare funding cut at the federal level. Host Carmel Crimms interviews Emanuel Saez, the UC Berkeley economist who co-designed the proposal, covering the measure's design, the resistance it faces, and what the outcome could mean for tax policy in the US and abroad.

■ The measure and its origins
- Why California is pursuing a billionaire tax as federal Medicaid funding shrinks
- How the design differs from past European wealth taxes
■ Design and enforcement
- How business ownership and publicly traded stock are valued and tracked
- Why the tax is structured as one-time and time-limited to reduce avoidance
■ The exodus debate
- Evidence on wealthy residents relocating under wealth taxes
- Whether Silicon Valley's ecosystem, not individuals, drives innovation
■ Politics and stakes
- Campaign spending by billionaires and the reaction of Democrats and unions
- Links between concentrated wealth and political influence
- What a win or loss would signal for future tax proposals

This episode suits viewers following US elections, tax policy, or debates over wealth inequality. It provides context for evaluating the measure and for understanding the broader argument over how democracies tax extreme wealth, plus the answers to the show's Forbes 400 quiz.