Taking Others into Account: Self-Interest and Fairness in Majority Decision Making


  • We thank Jens Grosser for his invaluable advice on the experimental design. We further thank Rebecca Morton, Bernhard Kittel, and Wolfgang Luhan for comments on earlier versions of this article and Ulrich Glassmann for his assistance in the laboratory. Suggestions of the journal's editor and several anonymous referees were particularly helpful to improve the article. Financial support from the Max Planck Institute for the Study of Societies and from the German Research Foundation (DFG) for the Cologne Laboratory for Economic Research is also gratefully acknowledged.

Jan Sauermann is a doctoral student at the International Max Planck Research School on the Social and Political Constitution of the Economy (IMPRS-SPCE), University of Cologne, Department of Political Science, P.O. Box 41 10 20, 50870 Cologne, Germany (jan.sauermann@uni-koeln.de). André Kaiser is Professor of Political Science, University of Cologne, P.O. Box 41 10 20, 50870 Cologne, Germany (andre.kaiser@uni-koeln.de).


Research on the formal properties of democratic aggregation mechanisms has a long tradition in political science. Recent theoretical developments, however, show that in the discussion of normative contents of democratic decisions, the actual shape of preferences deserves just as much attention. However, our knowledge about the concrete motivations of individual behavior in democratic decisions is incomplete. Using laboratory experiments, this article examines the existence of social preferences in majority decisions. Contrary to earlier experiments of committee decision making, we develop a design that controls for the conditions of communication and the level of information between subjects. This allows us to comparatively test the predictive power of several theories. We find strong evidence that self-interest and fairness motivate human behavior in majority decisions.