A House Divided

Abstract

Mixed-member electoral systems embrace two views of representation by electing some legislators in single-member district elections and others in a proportional representation election. This can potentially create a “mandate divide” in legislatures, because single-member district legislators have an incentive to embrace parochial issues and proportional representation legislators have an incentive to center on national issues. Previous studies of this question have only found limited evidence of its existence. The author argues that the level of party system institutionalization will fundamentally determine whether a mandate divide will exist in a mixed-member legislature. Using roll-call voting data from the Hungarian National Assembly, the Russian Duma, and the Ukrainian Rada, the author analyzes patterns of party discipline in each legislature. The empirical results show that a mandate divide only existed in the legislature with the most weakly institutionalized party system, the Russian Duma.