This paper presents a laboratory experiment to investigate how social motivations and free-form communication (Rich Communication) can facilitate coordinated resistance against divide-and-conquer transgressions. In our experiment, a leader first decides whether to extract surplus from a victim...

Costless pre-play communication has been found to effectively facilitate coordination and enhance efficiency in games with Pareto-ranked equilibria. We report an experiment in which two groups compete in a weakest-link contest by expending costly efforts. Allowing intra-group communication leads...