When a person recognises their own and others' position in a social hierarchy, leading to recognition of the authority figure's right to issue a demand
Bickman found that people were twice as likely to obey someone in a security guard's uniform as someone not wearing one (jacket + tie) because the uniform gave them legitimacy of authority
Affected legitimacy of authority - the scientific laboratory meant that more people obeyed than in run-down office blocks which reduced the legitimacy of authority that the experimenter had