Four studies tested the proposition that regulation of collective guilt in the face of harmful ingroup behavior involves motivated reasoning. Cognitive energetics theory suggests that motivated reasoning is a function of goal importance, mental resource availability, and task demands. Accordingly, three studies conducted in the United States and Israel demonstrated that high importance of avoiding collective guilt, represented by group identification (Studies 1 and 3) and conservative ideological orientation (Study 2), is negatively related to collective guilt, but only when mental resources are not depleted by cognitive load. The fourth study, conducted in Italy, demonstrated that when justifications for the ingroup’s harmful behavior are immediately available, the task of regulating collective guilt and shame becomes less demanding and less susceptible to resource depletion. By combining knowledge from the domains of motivated cognition, emotion regulation, and intergroup relations, these cross-cultural studies offer novel insights regarding factors underlying the regulation of collective guilt.