Calling European Union Treaty Referendums: Electoral and Institutional Politics

Abstract

Many European integration treaties – most notably the failed Constitutional Treaty – have faced ratification by referendum in various member states. Although the literature on voting behaviour in these referendums in now well established, the reasons why these referendums were held in the first place is under-scrutinised. This article examines the reasons EU member states decide to call referendums in order to ratify EU treaties and argues that they do so primarily as a result of domestic political pressure arising from three sources: electoral pressure when the EU is unpopular and elections are close, rules governing the use of referendums, and domestic institutional veto players. This theory is tested using a combination of single and multi-level logistic regression analysis, which finds support for the hypotheses developed here.