The expression of emotion can play a significant role in strategic decision-making. In this study, we hypothesized that emotion expression alters behavior in morally charged negotiation. We investigated the impact of facial displays of discrete emotions, specifically anger and sadness, in a morally charged multi-issue negotiation task. Our results indicate that if a negotiator associated moral significance to the object of the negotiation, displays of anger resulted in reduced concession making whereas displays of sadness increased concession making. Moral significance of the issues fostered an emotional matching mechanism of sorrow, where a sorrow expression from one party elicited a sorrow expression from the other. Taken together, the results indicate that emotional expressions can affect morally charged negotiation in ways that can inhibit as well as promote cooperation
