Entrusting the power to punish to a central authority is a hallmark of civilization. We study a collective action dilemma in which self-interest should produce a sub-optimal outcome absent sanctions for non-cooperation. We then test experimentally whether subjects make the theoretically optimal...

The sanctioning of norm-violating behavior by an effective formal authority is an efficient solution for social dilemmas. It is in the self-interest of voters and is often favorably contrasted with letting citizens take punishment into their own hands. Allowing informal sanctions, by contrast,...