People are willing to punish others at a personal cost, and this apparently antisocial tendency can stabilize cooperation. What motivates humans to punish noncooperators is likely a combination of aversion to both unfair outcomes and unfair intentions. Here we report a pair of studies in which captive chimpanzees (Pan troglodytes) did not inflict costs on conspecifics by knocking food away if t...

The expectation that non-cooperators will be punished can help to sustain cooperation, but there are competing claims about whether opportunities to engage in higher-order punishment (punishing punishment or failure to punish) help or undermine cooperation in social dilemmas. In a set of experimental treatments, we find that availability of higherorder punishment increases cooperation and effic...

A number of experimental studies have shown that the opportunity to punish anti-social behavior increases cooperation levels when agents face a social dilemma. Using a public good experiment, I show that in the presence of counter-punishment opportunities cooperators are less willing to punish free riders. As a result, cooperation breaks down and groups have lower earnings in comparison to a tr...

The criminal justice system has traditionally been seen as in the business of doing justice: punishing offenders for crimes committed. Yet, the past decade has brought a shift from punishing past crimes to preventing future crimes through the incarceration and control of dangerous offenders. Habitual offender statutes, like "three strikes" laws, sentence repeat offenders to life imprisonment. J...