|We use a laboratory experiment to study the role of bystanders in bullying. We devise a simple repeated game played in groups of three subjects with one leader and two followers. At the beginning of each round, each subject receives the same initial endowment. Then the leader proposes to reallocate a certain portion of the endowment from a follower of her choice to herself. If the other follower, i.e. the bystander, agrees, the reallocation takes place. If the bystander disagrees (at zero additional cost), payoffs of all players equal to the initial endowment. This game is played repeatedly in a partner matching and with the same leader. The allocation of the role of the victim and bystander depends on leader’s choice in every round. The aim of the paper is to explore the motives of the bystander to agree with the unequal distribution. For this, we use two manipulations. First, we elicit social identity (SI) creating two teams of different colors, letting them wear different T-shirts and play a cooperative game in teams. In the treatment with different social identities, one follower is on the same team as the leader while the other follower is on the other team. In the treatment with the same SI, all players are from the same team. Second, the number of rounds played is either known (finitely repeated) or uncertain (infinitely repeated). The choices of bystanders in the last rounds of these treatments might reflect the bystander’s fear of retaliation from the side of the leader, as the bystander who disagrees with the proposed re-allocation might expect to become the victim in the next round. Our experiment shows that while the different social identity of the victim makes the bystander more likely to accept the unequal distribution, fear of retaliation has no significant effect on her choice.