Obedience to Rules with Mild Sanctions: The Roles of Peer Punishment and Voting

Governments sometimes promote rules backed by sanctions too weak to make obedience privately optimal. Factors that may help make such rules effective include the presence of informal sanctions by peers, and implementation through voting. I study the impact of non-deterrent formal sanctions on voluntary contributions to a public good in a laboratory experiment. The effect is studied both in the presence and absence of informal sanctions, under fully exogenous implementation and after both implemented and randomly overridden voting. I find that informal sanctions strengthen the effect of formal ones in most conditions. However, voted implementation has no clear effect on non-deterrent formal sanction in my data, which suggests a reason for caution when studying exogenous implementation by a random vote override procedure.