We examine optimal taxation and social insurance if insurance markets are imperfect. This requires the development of a theory of labor supply under uncertainty. We show that the case for social insurance is not generally reinforced by adverse selection in insurance markets as social insurance...

This paper analyzes Pareto optimal non-linear taxation of profits and labor income in a private information economy with endogenous firm formation. Individuals differ in both their skill and their cost of setting up a firm, and choose between becoming workers and entrepreneurs. I show that a tax...

This paper studies Pareto-optimal risk-sharing arrangements in a private information economy with aggregate uncertainty and ex ante heterogeneous agents. I show how to implement Pareto-optima as equilibria when agents can trade claims to consumption contingent on aggregate shocks in financial...

This paper studies optimal dynamic tax policy under the threat of political reform. A policy will be reformed ex post if a large enough political coalition supports reform; thus, sustainable policies are those that will continue to attract enough political support in the future. We find that...

Recent policy proposals have suggested taxing top incomes at very high rates on the grounds that some or all of the highest wage earners are engaged in socially unproductive or counterproductive activities, such as externality imposing speculation in the financial sector. To address this, we...

This paper studies optimal dynamic tax policy under the threat of political reform. A policy will be reformed ex post if a large enough political coalition supports reform; thus, credible policies are those that will continue to attract enough political support in the future. If the only...