On the veil-of-ignorance principle: welfare-optimal information disclosure in Voting

Résumé

Voters’ voting decisions crucially depend on their information. Thus, it is an important question how much / what kind of information they should know, as a normative guidance of the optimal extent of transparency. We consider a simple two-alternative majority voting environment, and study the optimal information disclosure policy by a utilitarian social planner. Although full transparency is sometimes (informally) argued as ideal, we show that full transparency is often strictly suboptimal. This is related to the well-known potential mis-match between what a majority wants and what is socially optimal. Under certain conditions, in order to alleviate this mismatch, the op-timal policy discloses just the “anonymized” information about the value of the alternatives to the voters, placing them effectively behind a partial “veil of ignorance”.