Challenging the standard reasoning regarding leaders' ethical failures we argue that a potent contributor to these failures is the social role expectations of leaders. We maintain that leaders' central role expectation of goal achievement contributes to the over-valuing of group goals and greater moral permissibility of the means used to achieve these goals. In studies 1 and 2 we demonstrated that the role of leader relative to group member is associated with an increased appraisal of group goalswhich is predicted by the leaders' role expectations and not driven by the psychological effects of power. Next we experimentally demonstrated the importance of both role expectations of leadership and group goal importance in leaders' justification to engage in morally questionable behavior to achieve group goals. Finally we supported the social role predictions in a laboratory experiment by assigning people to roles and assessing goal importance and unethical decision-making and behavior.