Moral opportunism as a consequence of decision making under uncertainty

When people with different normative beliefs interact, moral opportunism-or the tendency to follow the norm that brings the highest material benefit-can arise. Our conjecture is that this behavior is a consequence of expected norm-dependent utility maximization under uncertainty. Using a novel theoretical framework for studying social norms, we experimentally test this idea in the Dictator game with second-party punishment. The theory links normative beliefs and punishment strategies, which allows us to study what determines recipients' punishment choices after they are shown normative beliefs of their dictators. We corroborate the theory and find that many recipients indeed act in accordance with the maximization of expected norm-dependent utility that has a negative flavor of moral opportunism. We also find that some of the recipients are excessive punishers: they punish a lot, but not according to their normative beliefs. Excessive punishment is exhibited by recipients from Southern Europe, but not by recipients from the rest of Western Europe. (c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )