Some Complex Answers to the Simple Question ‘Do Institutions Matter?’

Much current research in political science focuses on the impact which political institutions have on policy outcomes. A substantial body of this ‘neo-institutional’ work, often organized around the question, ‘Do institutions matter?’, examines differences in the performance of presidential and parliamentary systems. The conventional wisdom in the literature has been that presidential and parliamentary systems tend to select different policies and exhibit different patterns of policy change. But the key question is whether the two different kinds of institutional systems should necessarily be expected to choose different policies or exhibit different patterns of policy change. This paper emphasizes that one cannot draw valid inferences about the nature of policy choice and policy change in different kinds of institutional systems just by considering the institutional rules alone. Instead, if we wish to compare the nature of policy choice and policy change in the different systems, it is essential to consider the interaction between the institutional rules and the policy preferences of the individual officeholders in these systems. And what must be compared involves the sets of policy equilibria produced by each of the systems. When these policy equilibria are systematically compared across institutional systems, the results about policy choice and policy change do not always support the inference that ‘institutions matter’.