P: De-individuation theory has practical application that allows for preventing aggression

E: For example, the introduction of street lighting and CCTV cameras due to the significance of anonymity in increasing aggression

E: This increases the validity of the explanation as it has proven to lead to beneficial change within society

P: Research support from Zimbardo

E: For instance, Zimbardo found that when participants felt anonymous, they were more likely to perform aggressive acts

E: This suggests that the anonymity provided by their clothing caused them to display aggressive behaviour, supporting the idea that deindividuation and loss of personal identity lead to aggression

P: There are ethical issues with researching aggression

E: For instance, in Zimbardo's experiment, many participants experienced psychological distress and anxiety

E: Thus, to research aggression, aggression must be encouraged which could cause harm to participants, making it difficult to research

P: De-individuation theory can't explain many types of aggression

E: For instance, it doesn't explain one-on-one aggression or aggression from individuals who aren't anonymous

E: This suggests that there must be other factors influencing why people perform aggressive behaviour