The Great Divide: Neither Fairness Nor Kindness Eliminates Moral Derogation of People With Opposing Political Beliefs

People increasingly view those with opposing political beliefs as less moral than those with shared political beliefs. Across two experiments, using a U.S. undergraduate sample (n = 1,070) and a U.S. resident online sample through Prolific (n = 402), we employed the Ultimatum Game (UG) to investigate whether acts of fairness, or even kindness, by persons with out-party political beliefs would mitigate moral derogation toward them. In neither experiment, did fairness or kindness by persons with opposite political beliefs moderate moral derogation. More extreme partisans engaged in even greater moral derogation of out-party (versus in-party) individuals, regardless of their acts of fairness or kindness. However, even self-identified moderate partisans engage in out-party moral derogation. The implications of these findings for political discourse and resolution for political conflict are discussed.