A trial in Jerusalem, an experiment in New Haven
The claim under test was stark: that ordinary people, given no threat and no direct coercion, would inflict serious harm on a stranger simply because a person in a position of authority told them to keep going. Stanley Milgram set up the study at Yale in 1961, three months after Adolf Eichmann’s trial began in Jerusalem, explicitly motivated by the question of how ordinary Germans could have participated in the Holocaust under orders. Volunteers were told they were taking part in a study of learning and punishment, and were assigned, through a rigged draw in which both slips actually read teacher, to administer what they believed were real electric shocks to another participant, in fact an actor, whenever that person answered a word-pairing question incorrectly.
Two slips, both rigged
The shocks were presented as rising in 15-volt increments from 15 up to 450 volts, with the actor in the learner’s role delivering pre-recorded protests, banging on the wall, and eventually falling silent as the supposed voltage climbed, while the actual experimenter, present in the room with the volunteer, instructed them to continue whenever they hesitated. No real shocks were ever delivered. Before running the study, Milgram surveyed psychiatrists about how far they expected participants to go, and they predicted that under four in a hundred, precisely 3.73 per cent, would continue past 300 volts. In the actual experiment, every participant in the original condition reached at least 300 volts, and 65 per cent went all the way to the maximum 450 volts, a result so far outside expert prediction that it became the study’s defining number.
A prediction that missed by a mile
What has held up, across dozens of later replications catalogued in a meta-analysis by Thomas Blass, is that high rates of obedience in this basic setup are a real, repeatable phenomenon rather than a one-off artefact of Milgram’s particular sample, with obedience across studies ranging from 28 to 91 per cent, averaging 61 per cent in the United States and 66 per cent outside it. The result also proved sensitive to circumstance in ways that have replicated consistently: obedience fell to 47.5 per cent when the study moved to a modest office setting rather than Yale itself, to 40 per cent when the volunteer and the learner were in the same room, and to 21 per cent when the experimenter delivered instructions only by telephone rather than in person. Jerry Burger’s 2009 partial replication, which stopped at 150 volts to satisfy modern ethical requirements, found obedience rates close to Milgram’s own from decades earlier.
Obedience that depended on distance
What has not held up without challenge is a simple reading of the result as proof that people blindly obey authority. Gina Perry argued in 2012 that only about half of participants fully believed the shock apparatus was genuine, and that among those who did believe it, 66 per cent actually refused to continue, a very different picture from the headline 65 per cent obedience figure if belief in the setup is factored in. More recent researchers, including Alexander Haslam and Stephen Reicher, have proposed that many participants continued not out of blind obedience but out of what they call engaged followership, a active identification with the experimenter’s scientific goals rather than passive submission to an order. The ethical criticism, led by Diana Baumrind in 1964, focused less on whether the result was real and more on whether Milgram’s informed consent adequately protected participants who showed visible signs of distress, sweating and trembling, during the study itself.
A study that changed how studies are run
The stakes of the finding extend well beyond the psychology laboratory: obedience research of this kind has been invoked to help explain events including the My Lai massacre and to inform how police interrogation and military command structures are trained to guard against unquestioning compliance. The ethical fallout mattered just as much practically, since the criticism the study attracted, including an initial delay in Milgram’s American Psychological Association membership over concerns about his methods, fed directly into the development of institutional review boards and informed consent standards that now govern human research broadly. Milgram himself reported that 84 per cent of former participants said afterward they were glad or very glad to have taken part, a figure defenders cite against claims of lasting harm, though critics regard it as insufficient justification on its own for the distress caused during the study itself.
Same result, tighter rules
Yes, and reading past the popular summary is worth the time specifically because the details complicate the story people usually repeat. The bare statistic, that most people will shock a stranger if told to, is only the entry point; the more interesting material is in how sharply that rate moved with distance, setting and physical presence, and in the genuine, ongoing argument among researchers about whether obedience to authority is even the right description of what participants were doing. It is also a rare case where the ethical controversy is as consequential as the scientific finding itself, since the rules that now protect participants in psychological research trace directly back to the objections this particular study provoked.