For brevity, we do not report our questionnaire results (interested readers may consult Fehr & Fischbacher, 2004), but they are consistent with the view that emotions cause the sanctioning decisions that enforce social norms, because the pattern of third-party punishment and the emotional pattern fit together nicely. However, the results do not prove that emotions cause the sanctioning decisions. We are aware that self-reported or predicted emotions need to be treated with caution. It is possible that self-reported emotions deviate systematically from the emotions that subjects actually would experience if they were in a particular scenario. However, our questionnaire results suggest at least interesting hypotheses regarding the role of emotions in norm enforcement.

QUESTION: Self-reported emotion data is not definitive proof; worth exploring whether experimental methods can establish causation between emotion and sanctioning.

Ernst Fehr, Third-Party Punishment and …, loc. 146