Efficient redistribution

What is the optimal shape of non-linear income and wealth taxes? We answer this question using a dynamic general equilibrium model with uninsurable idiosyncratic risk. Our analysis reproduces the distribution of income and wealth in the United States and takes into account the long-lived transition dynamics after policy reforms. We find that a uniform flat tax on capital and labor income combined with a lump-sum transfer is nearly optimal. The incremental welfare gains from steeper marginal income and wealth taxes are small, especially when the planner has a strong preference for redistribution, due to strong behavioral and general equilibrium effects.