What are the best quorum rules? A laboratory investigation

  • Luís Aguiar-ConrariaEmail author
  • Pedro C. Magalhães
  • Christoph A. Vanberg


Many political systems with direct democracy mechanisms have adopted rules preventing decisions from being made by simple majority rule. The device added most commonly to majority rule in national referendums is a quorum requirement. The two most common are participation and approval quorums. Such rules are responses to three major concerns: the legitimacy of the referendum outcome, its representativeness, and protection of minorities regarding issues that should demand a broad consensus. Guided by a pivotal voter model, we conduct a laboratory experiment to investigate the performances of different quorums in attaining such goals. We introduce two main innovations in relation to previous work on the topic. First, part of the electorate goes to the polls out of a sense of civic duty. Second, we test the performances of a different quorum, the rejection quorum, recently proposed in the literature. We conclude that, depending on the preferred criterion, either the approval or the rejection quorum is the best.


Election design Participation quorum Approval quorum Laboratory experiment 

JEL Classification

C91 D72 D02 



This paper is financed by National Funds of the FCT—Portuguese Foundation for Science and Technology within the projects UID/ECO/03182/2019 and UID/SOC/50013/2019, and the research grant PTDC/IVC-CPO/4925/2014, with the FCT/MEC’s (Fundação para a Ciência e a Tecnologia, I.P.) financial support through national funding and by the ERDF through the Operational Programme on “Competitiveness and Internationalization–COMPETE 2020” under the PT2020 Partnership Agreement.

Supplementary material

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Supplementary material 1 (DOCX 348 kb)


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Copyright information

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Authors and Affiliations

  1. 1.NIPE and Economics DepartmentUniversity of MinhoBragaPortugal
  2. 2.Institute of Social SciencesUniversity of LisbonLisbonPortugal
  3. 3.Alfred-Weber-InstitutUniversity of HeidelbergHeidelbergGermany

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