Conditional Party Government in the States

©2002 by the Midwest Political Science Association A lthough theories about legislative politics continue to proliferate, their range of empirical application is all too often limited, generally encompassing only the U.S. Congress or even just the House. Here, we conduct what is essentially comparative research by testing theories of parties and committees in a number of state legislatures. This provides us the variation to be able to examine current theories of the role of the political party in legislative politics and its connections to informational and partisan theories of legislative design. We combine some aspects of electoral politics to develop a measure of the effective number of parties, roll-call voting to estimate legislators’ preferences, and committee membership to examine the effects of differing levels of partisan polarization on the representativeness of committees. In the next section, we develop the relevant theoretical considerations. We then turn to data and measurement issues. The analytic sections then consider how closely state legislators satisfy the polarization condition in Aldrich and Rohde’s conditional party government account. We then examine these results with respect to the number of effective parties and the degree of partisan competition. That is, the electorate’s actions are compared to the distribution of (estimated) preferences among the winners of these elections. The third analytic section examines the impact of partisan competition and polarization on the distribution of legislators to committees. We find that there is substantial variation in the degree to which state legislatures meet Aldrich and Rohde’s polarization condition, extending far beyond the extreme values observed for the modern U.S. House. We find a strong negative relationship between the size of the majority party and the polarization of the parties. Finally, we find that chambers with more equally sized parties and more polarized parties tend to choose more representative committees. Conditional Party Government in the States