Committee Decision with Multiple Votes∗

Under what circumstances can a static voting mechanism aggregate dispersed information of committee members? I argue that whenever the voters are able to cast multiple votes, the quality of the joint decision increases. However, voting mechanisms are intrinsically additive ways of aggregating private information. This, naturally, is not a binding constraint if the private information is conditionally independent. However, if the ‘meaning’ of the private information depends on other members’ signals, i.e. the signals are conditionally correlated, then the joint decision by voting may be unsatisfactory. I relate this question to a representation problem in utility theory to derive abstract conditions on the joint signal distribution that are necessary and sufficient for efficient voting.