When giving justifies gambling: theory and experimental evidence on prosocial risk-taking

We study how altruistic motives interact with risk preferences in shaping economic behavior. In a laboratory experiment, we introduce a novel “prosocial risk” condition in which participants can choose between a safe option and a risky lottery, with potential gains donated to charity. We find that men become significantly more risk-seeking in this setting, while women become more risk-averse. These effects are not driven by beliefs about karma or magical thinking, but by the strategic use of altruism as a moral excuse: men use it to justify risk-taking, women to justify restraint. We formalize this mechanism into a structural model of altruistic utility that accounts for individual attitudes toward risk and estimate it using incentivized measures of altruism and optimism. Our results reveal a gendered asymmetry in moral self-signaling under risk and suggest that prosocial framing can systematically distort attitudes toward risk.