Voting Procedures for Complex Collective Decisions. An Epistemic Perspective

Abstract. In addressing a complex issue that is decomposable into several sub‐questions, a committee can use different voting procedures: Either it can let the committee members vote on each sub‐question and then use the outcomes as premises for its conclusion on the main issue (premise based‐procedure, pbp), or it can let the members directly vote on the conclusion (conclusion‐based procedure, cbp). The procedures can lead to different results, but which of them is a better truth‐tracker? On the basis of Condorcet's jury theorem, we show that the pbp is clearly superior if the objective is to reach truth for the right (= correct) reasons. However, if the goal instead is to reach truth for whatever reasons, right or wrong, there will be cases in which using the cbp turns out to be more reliable, even though, for the most part, the pbp will retain its superiority. In that connection, we also consider the truth‐tracking potential of a “sophisticated” variant of the pbp, which is sensitive to the size of the majorities supporting each of the premises.