This paper compares two methods to encourage socially optimal provision of a public good. We compare the efficacy of vigilante justice, as represented by peer-to-peer punishment, to delegated policing, as represented by the "hired gun" mechanism, to deter free riding and improve group welfare....

We present and experimentally test a mechanism that provides a simple, natural, low cost, and realistic solution to the problem of compliance with socially determined efficient actions, such as contributing to a public good. We note that small self-governing organizations often place enforcement...