"An Incentive-Compatible Utilitarian Voting Procedure for Permanent Citizens’ Assemblies"

Abstract :
We consider a committee of voters randomly drawn from a larger population facing an infinite sequence of voting decisions, akin to a citizen jury. We propose a new voting mechanism for such juries where each voter has a privately known von Neumann-Morgenstern (vNM) utility function over social alternatives in each decision, and is asked to report a real-valued ‘valuation’ for each alternative of a decision. We further impose a probability of being removed from the committee for the next decision dependent on the report of a voter. If a voter is removed, then they are replaced by some non-committee member from the larger population. We show that when the voters’ discount factor is large enough, imposing a probability equal to a scalar multiple of the Vickrey-Clarke-Groves tax leads to truthful revelation by the voters and consequently utilitarian efficient outcomes at a Bayesian Nash equilibrium.