Hurting you hurts me too: the psychological costs of complying with ostracism.

Much research has documented the harmful psychological effects of being ostracized, but research has yet to determine whether compliance with ostracizing other people is psychologically costly. We conducted two studies guided by self-determination theory to explore this question, using a paradigm that borrows from both ostracism research and Milgram's classic study of obedience. Supporting our guiding hypothesis that compliance with ostracizing others carries psychological costs, the results of Experiment 1 showed that such compliance worsened mood compared with complying with instructions to include others and with receiving no instructions involving inclusion or exclusion, an effect explained by thwarted psychological needs resulting from ostracizing others. Experiment 2 revealed increases in negative affect both when individuals ostracized others and when individuals were ostracized themselves. Our findings point to the robust psychological costs associated with ostracizing other people, with implications for group behaviors.