1. Alternative social explanations of group displays of aggression

2. Deindividuation theory
The deindividuation theory says that when people are in a large group they lose their sense of identity. They lose their private self-awareness as they belong to the group. Research by Diener has supported this theory. The study included a naturalistic observation of 1,300 trick-or- treating children in the US. When the children were wearing costumes which hid their identity and were in a large group they were more likely to perform anti-social acts. However the theory is deterministic as it does not allow for free-will and the fact that some individuals chose not to behave aggressively when they are apart of a large group.

3. Social learning theory
This theory explains aggression of large groups by the members of the group observing another member being rewarded for aggressive actions. This is vicarious reinforcement. The individuals in the group will access whether they are personally able to reproduce the same aggressive behaviour to achieve the same rewards. This is known as self-efficacy. This can be used to explain how aggressive behaviour comes about it large groups. This theory can be reductionist as it does not account for biological explanations and also it is deterministic as it is implicated that an individual will copy the behaviour of the model when they observe the aggressive behaviour being rewarded.