Self-Enforcing Partisan Procedures

Using a multistage model of collective decision making, we study how partisan polarization in legislatures affects the initial choice and future revision of procedural rules. We analyze how a legislature allocates proposal power over policy decisions under uncertainty about the future polarization in policy preferences among legislators. Our notion of polarization encompasses both intra- and interparty heterogeneity in policy preferences. We show that majority procedures are partisan and self-enforcing, that is, survive future revisions even though they concentrate proposal power in the hands of a few (nonmedian) majority party members. This leads to systematic promajority policy bias. Increased polarization, however, may not increase the concentration of proposal power within the majority party. The model provides a unified analytical framework to evaluate a long-standing debate about the foundations of partisan influence in the US Congress.