Much of the research in the experimental and behavioral sciences finds that stronger prosocial norms lead to higher levels of prosocial behavior. Here, we show that very strict prosocial norms are negatively correlated with prosocial behavior. Using laboratory experiments on honesty, we demonstrate that individuals who hold very strict norms of honesty are more likely to lie to the maximal extent. Further, countries with a larger fraction of people with very strict civic norms have proportionally more societal-level rule violations. We show that our findings are consistent with a simple behavioral rationale. If perceived norms are so strict that they do not differentiate between small and large violations, then, conditional on a violation occurring, a large violation is individually optimal.
