When sanctions fail to increase cooperation in social dilemmas: considering the presence of an alternative option to defect.

Previous social dilemma research has shown that sanctioning defection may enhance cooperation. The authors argue that this finding may have resulted from restricting participants to two behaviors (cooperation and defection). In this article, the authors introduce the concept of a "social trilemma" (a social dilemma in which an alternative option to defect is present) and tested the effect of a sanction. The authors show that a sanction only increased cooperation and collective interests in the traditional social dilemma. In a social trilemma, the sanction failed because it caused some people to choose the alternative option to defect. Moreover, the results indicate that this was especially the case when people did not expect fellow group members to cooperate. In this case, the sanction even worked counterproductive because it decreased collective interests. It is concluded that allowing individuals to consider alternative options to defect can reveal the potential detrimental effects of sanctioning systems for the collective.