Committees and special interests

This paper studies the aggregation of decentralized information in committees nder open and closed voting in the presence of external influence. We show that under one-sided influence decision quality may be nonmonotonic in the committee members' ability. Furthermore, restricting the information of interest groups may reduce the bias toward special interest politics. This result holds in a single and in a common agency setting, where opposing interest groups' activities do not cancel out in equilibrium. Moreover, there are cases where benefits from increasing the number of decision makers can only be reaped if the committee's sessions are not public.