Commitment Problems in Coalitions: A New Look at the Fiscal Policies Of Multiparty Governments

Many political scientists and economists have argued that coalition governments tend to accumulate more debt than single-party governments do, but the evidence for this proposition is mixed. This article argues that only some coalition governments are more likely to increase public debt than single-party governments: those in which parties are unable to make credible promises to their partners about future policy. It introduces the concept of ‘commitment potential’ within coalitions and proposes a way of measuring it. The study evaluates its theoretical claims using data on 20 advanced democracies observed over a period of almost 50 years. It finds that multiparty governments with high commitment potential do not, on average, accumulate more debt than single-party governments, but that governments with low commitment potential do.