To test uniform, instead of having the experimenter wear a grey lab coat (a type of uniform and a symbol of his authority), like in the original study, the experimenter was taken over by an 'ordinary member of the public' (one of Milgram's confederates) in every day clothes. The obedience rate dropped to 20%- the lowest of the variations. This tells us that people are more likely to obey when someone is wearing a uniform because they see their authority as legitimate (ie it is granted by society). Uniforms encourage our obedience because they are widely recognised as symbols of authority; someone without a uniform has less right to expect our obedience.