Coalitions in Presidential Systems: Rethinking the ‘Partisan Assumption’

The assumption that government coalitions reflect parliamentary coalitions has been the bedrock of work on government formation in both parliamentary and presidential systems. While in the former, the dependence of the government on parliamentary majorities for their survival underpins this assumption, in presidential systems researchers have argued that the need to pass legislation gives presidents incentives to act in ways very similar to their parliamentary counterparts. Faced with minority support in congress, presidents allocate cabinet positions to members of political parties that, in exchange for participating in the government, agree to support the president’s legislative agenda. Empirical work, however, has not put this assumption to the test. Most existing work defines partisanship as binary (partisan/non-partisan) and uses this information to decide whether the president has formed a governing coalition or not. But this literature has rarely gone beyond a simple coding of whether individual ministers are associated with a political party in the legislature, to look more carefully at whether they actually have the active support of that party and the explicit charge to represent the party’s interests in the cabinet. In this paper we use original data on the degree to which members of the cabinet are ‘strict partisans’–or active members of a ‘relevant’ political party–to revisit the formation of coalitions in Latin America. Through careful coding of party membership, we show that degrees of partisanship have important consequences for how we identify and count presidential coalitions and, thus, for our understanding of coalition government in presidential systems.