On the determinants of referendum boycotts in Europe: democracy, quorum rules, and party motivations

Abstract In the contemporary ‘age of participation’, referendums are often celebrated as cornerstones of democratic engagement. Yet political parties sometimes take the seemingly paradoxical step of calling for referendum boycotts, urging citizens to abstain from direct democratic processes. This paper investigates the conditions under which such boycott calls occur and the motivations behind them. While previous research has largely focused on single cases or experimental designs, we offer the first comprehensive, comparative study of party-led referendum boycotts across Europe since 1972. Drawing on a novel dataset of 223 referendums in 37 countries, we combine quantitative and qualitative methods to explore how regime context, institutional design, and issue type shape boycott behavior. Our regression analyses show that turnout quorum requirements, lower levels of democratic maturity, and sovereignty-related referendum issues significantly increase the likelihood of boycotts. To complement these findings, we qualitatively analyze boycott justifications and develop a typology of six motivation types: legitimacy-based, procedural unfairness, instrumental, tactical, minority interest, and ideological boycotts. These results reveal a complex interplay between democratic institutions and political strategy, challenging the assumption that referendums are universally inclusive tools. Our findings have implications for the design, interpretation, and normative evaluation of direct democratic practices across diverse political systems.