Previous theory and research suggests that perceiving shared humanity with others should be a positive force for intergroup relations. The present research considers the alternative possibility, that notions of shared humanity might protect people from feelings of guilt over ingroup perpetrated harm by obscuring the ingroup's unique role in these events. Consistent with this idea, Study 1 (N=58) found that perceiving shared humanity with a harmed outgroup was associated with less guilt and stronger expectations of forgiveness among members of the perpetrator group. Study 2 (N=52) demonstrated that these effects only occurred when the moral integrity of the ingroup was open to question. When ingroup morality was instead secure, defensive use of humanity was not apparent. Together, these studies suggest that perceiving harmful ingroup actions as 'only human' can sometimes be a moral defence that absolves group members of feelings of responsibility for wrongdoing.