Social scientists have proposed that expectations about leadership-based power asymmetries have gradually evolved over the course of human history. Some of these expectations concern leaders’ responsibilities to their followers. In particular, leaders are expected to intervene in within-group transgressions and confront the wrongdoers. In violation-of-expectation experiments, we examined whether 17-mo-old infants would share this expectation about leaders. When a fairness transgression occurred among a group of bear puppets, infants expected a leader to intervene and rectify this transgression, but they held no particular expectation for intervention from a nonleader. Thus, consistent with claims that abstract expectations about leaders’ responsibilities are part of the human endowment, our findings indicate that such expectations are already present by the second year of life.