“I Vote With My Party”: Party Organization and Legislative Behavior in Brazil

Abstract

As a central element in the functioning of party governments, legislative party unity and discipline are usually explained through macro institutional factors and variables that are endogenous to the legislative process. However, parliamentarians are usually elected through party lists and there are differences among their parties in terms of decision-making structure and organizational strength. Drawing on evidence from Brazil, this article analyzes the effects of intraparty democracy (AIPD) and party strength (PSI: members, money, and local branches) on the levels of legislative party unity and discipline. The results of multivariate analysis suggest that the less democratic and the more robust the party organizations are, the greater the levels of legislative party unity and discipline. While organizational strength indicates to parliamentarians the potential consequences (amount of resources) of defecting and free-riding behavior, the level of intraparty democracy influences the effectiveness of enforcement mechanisms for punishing the legislators (access to resources). The findings suggest that differences among party organizations may be associated with different levels of party unity and loyalty in the legislature.