Exploiting moral wiggle room: experiments demonstrating an illusory preference for fairness

This paper explores whether generosity in experiments is truly evidence of concern for desirable social outcomes. We conduct an experiment using a binary version of the dictator game. We introduce several treatments in which subjects are able to leave the relationship between their actions and resulting outcomes uncertain, either to themselves or to another subject influenced by those actions, thus giving subjects the moral "wiggle room" to behave self-interestedly. We find significantly less generous behavior in these manipulations, relative to a baseline in which the relationship between actions and outcomes is transparent. We conclude that many subjects behave fairly in the baseline case mainly because they intrinsically dislike appearing unfair, either to themselves or others.