Political analysts have suggested that policy power will begin to shift from the federal government to state governments as gridlock in Congress persists. Therefore, understanding the policymaking process at the state level is more important than ever. Vitally missing from our understanding of policymaking in the states is the role of constitutional provisions. Many state constitutions contain directives that severely limit the ability of the legislature to act. Some of these directives are procedural while others are more substantive. This is relevant because constitutional rules are more difficult for members to alter than chamber rules. In this paper we present a quantitative measure of constitutional restrictiveness and explore the variation in this measure across the fifty state legislatures and the U.S. Congress. We discover that constitutional restrictiveness is largely explained by the historical era in which the most recent constitution has been passed
