Biased Experts, Majority Rule, and the Optimal Composition of Committee

Abstract

A committee of experts votes between a multi-attribute alternative and status quo. Each expert is a biased specialist who can privately evaluate only one attribute and puts more weight on it. We study whether a social-minded principal would compose the committee of more or less biased experts. We find that due to strategic voting, her optimal composition depends non-monotonically on the majority rule. The composition is, however, less crucial if experts can be uninformed. Nonetheless, the principal may prefer to have some uninformed experts, perhaps by rushing the vote, when the committee is large, or its composition is suboptimal.