Moral judgements of fairness-related actions are flexibly updated to account for contextual information.

In everyday life we are constantly updating our moral judgements as we learn new information. However, this judgement updating process has not been systematically studied. We investigated how people update their moral judgements of fairness-related actions of others after receiving contextual information regarding the deservingness of the action recipient. Participants (N = 313) observed a virtual 'Decision-maker' share a portion of $10 with a virtual 'Receiver'. Participants were aware that the Decision-maker made these choices knowing the Receiver's previous offer to another person. Participants first made a context-absent judgement of the Decision-maker's offer to the Receiver, and then a subsequent context-present judgement of the same offer after learning the Receiver's previous offer. This sequence was repeated for varying dollar values of Decision-makers' and Receivers' offers. Patterns of judgements varied across individuals and were interpretable in relation to moral norms. Most participants flexibly switched from relying on context-independent norms (generosity, equality) to related, context-dependent norms (relative generosity, indirect reciprocity) as they integrated contextual information. Judgement of low offers varied across individuals, with a substantial minority of participants withholding their context-absent judgements of selfishness, and another minority that was lenient towards selfishness across both judgements. Our paradigm provides a novel framework for investigating how moral judgements evolve in real time as people learn more information about a given situation.