In Milgram’s original research, which took place at Yale University, the percentage of participants administering the full 450 volts was high (65%).
However, when the experiment took place in a run down building in Bridgeport, Connecticut, obedience levels dropped significantly (48%).
This change in location reduced the legitimacy of the authority, as participants were less likely to trust the experiment.
In addition, when the experimenter in Milgram’s research was replaced by another participant, in ordinary clothes, the obedience levels dropped even further (20%).
The lack of a uniform and questionable position of authority reduced the credibility of the authority, which meant the participants were far less likely to obey.