Norm Enforcement in the city: A natural field experiment

The willingness of individuals to enforce social norms can have important welfare implications. All the experimental evidence on norm enforcement so far comes from laboratory experiments and indicates that many participants are indeed willing to enforce norms, even in one-shot interactions. We examine individuals’ willingness to punish norm violations in a natural field experiment. We violate two efficiency-enhancing norms in the main subway station in Athens, Greece. The large number of passengers ensures that strategic motives for punishing are minimized. We find that some individuals punish norm violators,but the rate of enforcement is low relative to that found in laboratory experiments. Surprisingly, violations of the better known of the two norms are less likely to trigger punishment. Questionnaire data indicate that most people are concerned about being counterpunished, and that violators of the better known norm are considered more likely to counterpunish.Men are more likely to punish than women, while the rate of enforcement is unaffected by the violator’s height and gender.