The premises of Condorcet's jury theorem are not simultaneously justified

Dietrich, Franz (2008) The premises of Condorcet's jury theorem are not simultaneously justified.

Abstract

Condorcet's famous jury theorem reaches an optimistic conclusion on the correctness of majority decisions, based on two controversial premises about voters: they should be competent and vote independently, in a technical sense. I carefully analyse these premises and show that: (i) whether a premise is justified depends on the notion of uncertainty or probability employed; (ii) no such notion renders both premises simultaneously justified. Especially the independence assumption should be weakened.