Flexibility or Stability? Analyzing Proposals to Reform the Separation of Powers

The social welfare effects of legislatures in presidential systems, such as the U.S. Congress, are frequently lamented. In response, there are proposals to reform the separation of powers system by giving presidents control of the legislative agenda and weakening rules such as the filibuster. We provide a game‐theoretic analysis of the policy and social welfare consequences of a more executive‐centric system. Integrating standard assumptions about legislative and executive incentives into a dynamic model of decision making with private investment, we show there are a variety of conditions under which stronger executives do not produce better outcomes. Moreover, we characterize how these conditions depend on factors such as the stability of the policymaking environment or investment fundamentals. Our findings are robust and consistent with empirical observations that U.S. policy outputs are not necessarily worse than those of nations with stronger executives, which more closely approximate prominent proposals by populist‐oriented reformers.