The majority of research on emotion and moral decisionmaking has focused on the intrapersonal effects of emotion. However, witnessing and displaying emotional expressions is also known to play a significant role in the facilitation and coordination of our social interactions. In this work, we hypothesize that interpersonal emotions effect moral appraisals by prioritizing different moral concerns. We investigate the impact of facial displays of discrete emotions, specifically anger and sadness, in a morally charged multiitem negotiation task. The results of our experiment support our hypothesis that moral appraisals can be strongly affected by interpersonal emotional expressions. We show that displays of anger may backfire if one of the parties associates moral significance to the objects of the negotiation, whereas displays of sadness promote higher concession-making. Overall, we argue that emotional expressions can shift moral concerns within a negotiation in ways that can promote cooperation.