--- - |2 Intergroup emotions motivate behavior, yet little is known about how people perceive these emotional experiences in others. In three experiments (Ns = 109, 179, 246), we show that U.S. citizens believe collective guilt is an illegitimate emotional motivator for ingroup political behavior, while collective pride is legitimate. This differential legitimacy is due to the perception that collective guilt violates the norm of group interest, while collective pride adheres to it; those who believe ingroup interests are more important than outgroups’ exhibited this illegitimacy gap. The perception that the intergroup emotion promoted ingroup entitativity mediated the relationship between emotion (pride vs. guilt) and legitimacy; this relationship was especially strong for those high in the belief in the norm of group interest. Collective guilt can have prosocial consequences, yet the perception that it is illegitimate may hinder such consequences from being realized. - Political Psychology, EarlyView.