In perhaps the most famous study ever conducted in social psychology, approximately two-thirds of men studied were willing to administer a lethal shock of electricity to a helpless victim when they were ordered to do so by a person who appeared to be in a position of authority.
This experiment, called the Milgram experiment, was carried out by Stanley Milgram, a psychologist at Yale University. The experiment focused on the conflict between obedience to authority and personal conscience.