Domestic Institutions and the Ratification of International Agreements in a Panel of Democracies

Abstract

A recent literature explores how domestic institutions affect politicians’ incentives to enter into international agreements (IAs). We contribute to this field by systematically testing the impact of a broad set of domestic institutional design features. This approach allows us to compare new and established political economy explanations of IA entry. For this purpose, 103 democracies are analyzed over the period 1975 to 2010. We find that domestic institutions determine countries’ disposition to enter into IAs, as predicted by political economic theory. For example, democracies with majoritarian electoral institutions have lower IA ratification rates than other democracies. Countries also ratify more IAs when their democratic institutions are long-lived and they lack an independent judiciary. However, programmatic parties and the number of domestic veto players are not associated with IA ratification. The key take-away of this study is that domestic institutions matter for how frequently states conclude formal deals with each other.