If an authority figure ordered you to deliver a 400-volt electrical shock to another person, would you follow orders? Most people would answer with an adamant "no." However, the Milgram obedience experiment aimed to prove otherwise.

During the 1960s, Yale University psychologist Stanley Milgram conducted a series of obedience experiments that led to some surprising results. These results offer a compelling and disturbing look at the power of authority and obedience.

More recent investigations cast doubt on some of the implications of Milgram's findings and even question the results and procedures themselves. Despite its problems, the study has, without question, significantly impacted psychology.

What Were the Milgram Experiments?

"The social psychology of this century reveals a major lesson: often it is not so much the kind of person a man is as the kind of situation in which he finds himself that determines how he will act." - Stanley Milgram, 1974

Milgram started his experiments in 1961, shortly after the trial of the World War II criminal Adolph Eichmann had begun. Eichmann’s defense that he was merely following instructions when he ordered the deaths of millions of Jews roused Milgram’s interest.

In his 1974 book "Obedience to Authority," Milgram posed the question, "Could it be that Eichmann and his million accomplices in the Holocaust were just following orders? Could we call them all accomplices?"

An Experiment of Shocking Proportions

The participants in the most famous variation of the Milgram experiment were 40 men recruited using newspaper ads. In exchange for their participation, each person was paid $4.50.

Milgram developed an intimidating shock generator, with shock levels starting at 30 volts and increasing in 15-volt increments all the way up to 450 volts. The many switches were labeled with terms including "slight shock," "moderate shock" and "danger: severe shock." The final two switches were labeled simply with an ominous "XXX."

Each participant took the role of a "teacher" who would then deliver a shock to the "student" whenever an incorrect answer was given. While the participant believed that he was delivering real shocks to the student, the “student” was a confederate in the experiment who was simply pretending to be shocked.

As the experiment progressed, the participant would hear the learner plead to be released or even complain about a heart condition. Once they reached the 300-volt level, the learner would bang on the wall and demand to be released. Beyond this point, the learner became completely silent and refused to answer any more questions. The experimenter then instructed the participant to treat this silence as an incorrect response and deliver a further shock.

Most participants asked the experimenter whether they should continue. The experimenter issued a series of commands to prod the participant along:

"Please continue." "The experiment requires that you continue." "It is absolutely essential that you continue." "You have no other choice; you must go on."

Did the Majority Deliver the Maximum Shock?

The measure of obedience was the level of shock that the participant was willing to deliver. How far do you think most participants were willing to go?

When Milgram posed this question to a group of Yale University students, it was predicted that no more than 3 out of 100 participants would deliver the maximum shock. In reality, 65 percent of the participants in Milgram’s study delivered the maximum shocks.

Of the 40 participants in the study, 26 delivered the maximum shocks while 14 stopped before reaching the highest levels. It is important to note that many of the subjects became extremely agitated, distraught, and angry at the experimenter, but they continued to follow orders all the way to the end.

Due to concerns about the amount of anxiety experienced by many of the participants, everyone was debriefed at the end of the experiment. The researchers explained the procedures and the use of deception.

However, many critics of the study have argued that many of the participants were still confused about the exact nature of the experiment. Milgram later surveyed the participants and found that 84 percent were glad to have participated while only 1 percent regretted their involvement.

The Moral Questions Milgram Raised

While Milgram’s research raised serious ethical questions about the use of human subjects in psychology experiments, his results have also been consistently replicated in further experiments. Thomas Blass (1999) reviewed further research on obedience and found that Milgram’s findings hold true in other experiments.

Why did so many of the participants in this experiment perform a seemingly sadistic act when instructed by an authority figure? According to Milgram, there are some situational factors that can explain such high levels of obedience:

The physical presence of an authority figure dramatically increased compliance.

The fact that Yale (a trusted and authoritative academic institution) sponsored the study led many participants to believe that the experiment must be safe.

The selection of teacher and learner status seemed random.

Participants assumed that the experimenter was a competent expert.

The shocks were said to be painful, not dangerous.

Later experiments conducted by Milgram indicated that the presence of rebellious peers dramatically reduced obedience levels. When other people refused to go along with the experimenter's orders, 36 out of 40 participants refused to deliver the maximum shocks.

"Ordinary people, simply doing their jobs, and without any particular hostility on their part, can become agents in a terrible destructive process. Moreover, even when the destructive effects of their work become patently clear, and they are asked to carry out actions incompatible with fundamental standards of morality, relatively few people have the resources needed to resist authority," Milgram explained in "Obedience to Authority."

Milgram’s experiment has become a classic in psychology, demonstrating the dangers of obedience. The research suggests that situational variables have a stronger sway than personality factors in determining obedience. However, other psychologists argue that both external and internal factors heavily influence obedience, such as personal beliefs and overall temperament.

Researchers Replicate Milgram: Would People Still Obey?

In 2009, researchers conducted a study designed to replicate Milgram's classic obedience experiment. In an article published in the APS Observer, psychologist Jerry Burger of Santa Clara University and author of the study described how relevant Milgram's study is today:

"The haunting black-and-white images of ordinary citizens delivering what appear to be dangerous, if not deadly, electric shocks and the implications of the findings for atrocities like the Holocaust and Abu Ghraib are not easily dismissed. Yet because Milgram's procedures are clearly out-of-bounds by today's ethical standards, many questions about the research have gone unanswered. Chief among these is one that inevitably surfaces when I present Milgram's findings to students: Would people still act that way today?"

Burger made several alterations to Milgram's experiment.

The maximum shock level was 150-volts as opposed to the original 450-volts.

Participants were also carefully screened to eliminate those who might experience adverse reactions to the experiment.

The results of the new experiment revealed that participants obeyed at the same rate that they did when Milgram conducted his original study more than 40 years ago.

The January 2009 issue of American Psychologist also contained discussion from other psychologists about the possible comparisons between Milgram's experiment and Burger's study.

According to Arthur G. Miller, Ph.D. of Miami University, "...there are simply too many differences between this study and the earlier obedience research to permit conceptually precise and useful comparisons."

However, Alan C. Elms, Ph.D., of the University of California, Davis argued that the replication still had merit. Elms pointed out that while "direct comparisons of absolute levels of obedience cannot be made between the 150-volt maximum of Burger's research design and Milgram's 450-volt maximum, Burger's "obedience lite" procedures can be used to explore further some of the situational variables studied by Milgram as well as to look at additional variables," such as situational and personality differences.

Recent Criticisms and New Findings

Psychologist Gina Perry suggests that much of what we think we know about Milgram's famous experiments is only part of the story. While researching an article on the topic, she stumbled across hundreds of audiotapes found in Yale archives that documented numerous variations of Milgram's shock experiments.

Were Subjects Coerced?

While Milgram's reports of his process report methodical and uniform procedures, the audiotapes reveal something different. During the experimental sessions, the experimenters often went off-script and coerced the subjects into continuing the shocks.

"The slavish obedience to authority we have come to associate with Milgram’s experiments comes to sound much more like bullying and coercion when you listen to these recordings," Perry suggested in an article for Discover Magazine.

Few Participants Were Really Debriefed

Milgram's experiments have long been the source of considerable criticism and controversy. From the get-go, the ethics of his experiments were highly dubious. Participants were subjected to significant psychological and emotional distress.

Milgram suggested that the subjects were "de-hoaxed" after the experiments. However, Perry's findings revealed that of the 700 or so people who took part in different variations of his studies between 1961 and 1962, very few were truly debriefed.

A true debriefing would have involved explaining that the shocks weren't real and that the other person was not injured. Instead, Milgram's sessions were mainly focused on calming the subjects down before sending them on their way. Many left in a state of considerable distress. While the truth was revealed to some months or even years later, many were simply never told a thing.

Variations Led to Differing Results

Another problem is that the version of the study presented by Milgram and the one that's most often retold does not tell the whole story.

The statistic that 65 percent of people obeyed orders applied only to one variation of the experiment, in which 26 out of 40 subjects obeyed. In other variations, far fewer people were willing to follow the experimenters' orders and in some versions of the study, not a single participant obeyed.

Did They Know the "Learner" Was Faking?

Perry even tracked down some of the people who took part in the experiments as well as Milgram's research assistants. What she discovered is that many of his subjects had deduced what Milgram's intent was and knew that the "learner" was merely pretending.

Such findings cast Milgram's results in a new light. It suggests that not only did Milgram intentionally engage in some hefty misdirection to obtain the results he wanted but that many of his participants were simply playing along.

Perry later explained to NPR that retracing the steps of Milgram's research upended her attitudes and beliefs about one of the most famous and controversial figures in psychology.

"I regarded Stanley Milgram as a misunderstood genius who'd been penalized in some ways for revealing something troubling and profound about human nature," she told NPR. "By the end of my research, I actually had quite a very different view of the man and the research."

Obedience Depends on a Few Critical Factors

More recent work by researchers suggests that while people do tend to obey authority figures, the process is not necessarily as cut-and-dry as Milgram depicted it.

In a 2012 essay published in PLoS Biology, psychologists Alex Haslam and Stephen Reicher suggested the degree to which people are willing to obey the questionable orders of an authority figure depends largely on two key factors:

How much the individual agrees with the orders

with the orders How much they identify with the person giving the orders

While it is clear that people are often far more susceptible to influence, persuasion, and obedience than they would often like to be, they are far from mindless machines just taking orders.

Why Is Milgram's Study Still So Powerful?

So why does Milgram's experiment maintain such a powerful hold on our imaginations, even decades after the fact? Perry believes that despite all its ethical issues and the problem of never truly being able to replicate Milgram's procedures, the study has taken on the role of what she calls a "powerful parable."

Milgram's work might not hold the answers to what makes people obey or even the degree to which they truly obey. It has, however, inspired other researchers to explore what makes people follow orders and, perhaps more importantly, what leads them to question authority.