Many experiments have demonstrated the power of norm enforcement— peer monitoring and punishment—to maintain, or even increase, contributions in social dilemma settings, but little is known about the underlying norms that monitors use to make punishment decisions, either within or across groups. Using a large sample of experimental data, we empirically recover the set of norms used most often by monitors and show first that the decision to punish should be modeled separately from the decision of how much to punish. Second, we show that absolute norms often fit the data better than the group average norm often assumed in related work. Third, we find that different norms seem to influence the decisions about punishing violators inside and outside one's own group.

While the opportunity to punish selfish and reward generous behavior coexist in many instances in daily life, in most laboratory studies, the demand for punishment and reward are studied separately from one another. This paper presents the results from an experiment measuring the demand for reward and punishment by ‘unaffected’ third parties, separately and jointly. We find that the demand for costly punishment is substantially lower when individuals are also given the ability to reward. Similarly, the demand for costly reward is lower when individuals can also punish. The evidence indicates the reason for this is that costly punishment and reward are not only used to alter the material payoff of others as assumed by recent economic models, but also as a signal of disapproval and approval of others’ actions, respectively. When the opportunity exists, subjects often choose to withhold reward as a form of costless punishment, and to withhold punishment as a form of costless reward. We conclude that restricting the available options to punishing (rewarding) only, may lead to an increase in the demand for costly punishment (reward).

Democracies generate norms prescribing what behaviours and preferences are deemed acceptable. But what keeps these political norms in place? We expect that they are enforced by observers who disapprove of norm-breaching behaviour and are willing to apply sanctions that make it socially costly. We test this expectation with a survey in Spain, where respondents were shown pictures of individuals with different political views. We focus on norms against radical-right preferences, one of the most established political norms. In line with our expectations, individuals disapprove of radical-right preferences more than other political preferences. This makes them more likely to socially sanction those preferences, which they do mainly in indirect ways that do not force interaction with the person breaching the norm. We provide evidence on the individual-level predictors of norm enforcement. Our findings highlight the micro-level mechanisms by which social influence affects the behaviour of democratic citizens.

The persistence and strength of international norms are thought to depend partly on the willingness of actors to punish their violation, but norm enforcement is often inconsistent. This article investigates states’ use of economic sanctions in order to gain insight into the role of metanorms (norms about enforcing norms) in international politics and explain this inconsistency. The quantitative analyses examine patterns of economic sanctions and arms embargo practices across different security norms and reveal two central findings. First, international metanorms may accommodate important interstate relationships. Although severe human rights abuse, conflict, nuclear weapons development, and support for terrorist organisations tend to attract sanctions, they are infrequent in comparison with norm violations. Valued relationships between senders and targets seem to be an accepted limit to the pursuit of costly norm enforcement. Second, norm violations nevertheless remain rare, suggesting that factors other than the prospect of material punishment may encourage compliance. Indeed, by preserving interstate relationships, international metanorms may facilitate the engagement needed for socialisation and social pressures as alternative compliance mechanisms.