Evolutionary norm enforcement

Applying an indirect evolutionary approach with endogenous preference forma tion, we show that a legal system can induce players to reward trust even i f material incentives dictate to exploit trust. By analyzing the crowding o ut or crowding in of trustworthiness implied by various verdict rules, we c an assess how a court influences the share of kept promises of "truly" trus tworthy players who evolutionarily evolved as trustworthy and of opportunis tic players who are only trustworthy if inspired by material incentives.