In a prisoner’s dilemma experiment, compared with the case when the implicated parties are allowed to punish each other, both the cooperation rate and the earnings are lower when the enforcement of punishment requires approval from an independent third party.

We report data from a laboratory experiment using dictator games to inform individual preferences over punishment outcomes. We find that many people punish after receiving disadvantageous outcomes, and those who do systematically prefer to use punishment to create self-advantageous inequality.