Stanford prison experiment

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The Stanford prison experiment was a study of the psychological effects of becoming a prisoner or prison guard. The experiment was conducted in 1971 by a team of researchers led by psychologist Philip Zimbardo at Stanford University. Twenty-four undergraduates were selected out of 70 to play the roles of both guards and prisoners and live in a mock prison in the basement of the Stanford psychology building. The students who were assigned to be the prisoners were paid $15 a day as an incentive, which is worth about $80 per day in 2008 currency.

Prisoners and guards rapidly adapted to their roles, stepping beyond the boundaries of what had been predicted and leading to dangerous and psychologically damaging situations. One-third of the guards were judged to have exhibited "genuine" sadistic tendencies, while many prisoners were emotionally traumatized and two had to be removed from the experiment early. Finally, Zimbardo terminated the experiment because he realized that his experiment was unethical.

Ethical concerns surrounding the famous experiment often draw comparisons to the Milgram experiment, which was conducted in 1961 at Yale University by Stanley Milgram, Zimbardo's former college friend.

Tom Peters and Robert H. Waterman Jr wrote in 1981 that the Milgram Experiment in the 1960s and the later Zimbardo Experiment were frightening in their implications about the danger which lurks in the darker side of human nature.^[1]

[edit] Goals and methods

Zimbardo and his team set out to test the idea that the inherent personality traits of prisoners and guards were key to understanding abusive prison situations. Participants were recruited using an advertisement in the local newspapers and offered $15 a day, or $80 in current dollars. They were told they would participate in a two-week "prison simulation." Of the 70 respondents, Zimbardo and his team selected the 24 males whom they deemed to be the most psychologically stable and healthy. These participants were predominantly white and middle-class.

The "prison" itself was in the basement of Stanford's Jordan Hall, which had been converted into a mock jail. An undergraduate research assistant was the "warden" and Zimbardo the "superintendent". Zimbardo set up a number of specific conditions on the participants which he hoped would promote disorientation, depersonalization and deindividuation.

The researchers provided weapons -- wooden batons -- and clothing that simulated that of a prison guard -- khaki shirt and pants from a local military surplus store. They were also given mirrored sunglasses to prevent eye contact. Prisoners wore ill-fitting smocks and stocking caps. Guards called prisoners by their assigned numbers, sewn on their uniforms, instead of by name. A chain around their ankles reminded them of their roles as prisoners.

The researchers held an "orientation" session for guards the day before the experiment, during which they were told that they could not physically harm the prisoners. In The Stanford Prison Study video, quoted in Haslam & Reicher, 2003, Zimbardo is seen telling the guards, "You can create in the prisoners feelings of boredom, a sense of fear to some degree, you can create a notion of arbitrariness that their life is totally controlled by us, by the system, you, me, and they'll have no privacy… We're going to take away their individuality in various ways. In general what all this leads to is a sense of powerlessness. That is, in this situation we'll have all the power and they'll have none."

The participants who had been chosen to play the part of prisoners were "arrested" at their homes and "charged" with armed robbery. The local Palo Alto police department assisted Zimbardo with the arrests and conducted full booking procedures on the prisoners, which including fingerprinting and taking mug shots. At the prison, they were transported to the mock prison where they were strip-searched and given their new identities.

[edit] Results

Guards force prisoners to do push-ups, while another (standing) is made to sing.

The experiment quickly grew out of hand. Prisoners suffered — and accepted — sadistic and humiliating treatment from the guards. The high level of stress progressively led them from rebellion to inhibition. By experiment's end, many showed severe emotional disturbances.

After a relatively uneventful first day, a riot broke out on the second day. The guards volunteered to work extra hours and worked together to break the prisoner revolt, attacking the prisoners with fire extinguishers without supervision from the research staff.

Guards forced the prisoners to count off repeatedly as a way to learn their prison numbers, and to reinforce the idea that this was their new identity. Guards soon used these prisoner counts as another method to harass the prisoners, using physical punishment such as protracted exercise for errors in the prisoner count. Sanitary conditions declined rapidly, made worse by the guards refusing to allow some prisoners to use the bathrooms. Mattresses were a valued item in the spartan prison, so the guards would punish prisoners by removing their mattresses, leaving them to sleep on concrete. Some prisoners were forced to go nude as a method of degradation, and some were subjected to sexual humiliation, including simulated homosexual sex.

Zimbardo cited his own absorption in the experiment he guided, and in which he actively participated as Prison Superintendent. On the fourth day, some prisoners were talking about trying to escape. Zimbardo and the guards attempted to move the prisoners to the more secure local police station, but officials there said they could no longer participate in Zimbardo's experiment.

Several guards became increasingly cruel as the experiment continued. Experimenters said that approximately one-third of the guards exhibited genuine sadistic tendencies. Interestingly, most of the guards were upset when the experiment concluded early.

Zimbardo argued that the prisoner participants had internalized their roles, based on the fact that some had stated that they would accept parole even with the attached condition of forfeiting all of their experiment-participation pay. Yet, when their parole applications were all denied, none of the prisoner participants quit the experiment. Zimbardo argued they had no reason for continued participation in the experiment after having lost all monetary compensation, yet they did, because they had internalised the prisoner identity, they thought themselves prisoners, hence, they stayed.

Prisoner 416

When a replacement prisoner was introduced; Prisoner No. 416 and expressed concern about the treatment of the other prisoners, the guards responded with more abuse. When he refused to eat, saying he was on a hunger strike, guards confined in a closet and called it solitary confinement, ^[2] The guards used this incident to turn the other prisoners against No. 416, saying the only way he would be released from solitary confinement was if they gave up their blankets and slept on the cold floor, which all but one refused to do.

Zimbardo concluded the experiment early when Christina Maslach, a graduate student he was then dating (and later married), objected to the appalling conditions of the prison after she was introduced to the experiment to conduct interviews. Zimbardo noted that of more than fifty outside persons who had seen the prison, Maslach was the only one who questioned its morality. After only six days of a planned two weeks' duration, the Stanford Prison experiment was shut down.

[edit] Conclusions

The Stanford experiment ended on August 20, 1971, only 6 days after it began instead of the 14 it was supposed to have lasted. The experiment's result has been argued to demonstrate the impressionability and obedience of people when provided with a legitimizing ideology and social and institutional support. It is also used to illustrate cognitive dissonance theory and the power of authority.

In psychology, the results of the experiment are said to support situational attributions of behaviour rather than dispositional attribution. In other words, it seemed the situation caused the participants' behaviour, rather than anything inherent in their individual personalities. In this way, it is compatible with the results of the also-famous Milgram experiment, in which ordinary people fulfilled orders to administer what appeared to be damaging electric shocks to a confederate of the experimenter.

Shortly after the study had been completed, there were bloody revolts at both the San Quentin and Attica prison facilities, and Zimbardo reported his findings on the experiment to the U.S. House Committee on the Judiciary.

[edit] Criticism of the experiment

The experiment was widely criticized as being unethical and bordering on unscientific. Current ethical standards of psychology would not permit such a study to be conducted today. The study would violate the American Psychological Associate Ethics Code, the Canadian Code of Conduct for Research Involving Humans, and the Belmont Report. Critics including Erich Fromm challenged how readily the results of the experiment could be generalized. Fromm specifically writes about how the personality of an individual does in fact affect behaviour when imprisoned (using historical examples from the Nazi concentration camps). This runs counter to the study's conclusion that the prison situation itself controls the individual's behaviour. Fromm also argues that the amount of sadism in the "normal" subjects could not be determined with the methods employed to screen them.

Because it was a field experiment, it was impossible to keep traditional scientific controls. Zimbardo was not merely a neutral observer, but influenced the direction of the experiment as its "superintendent". Conclusions and observations drawn by the experimenters were largely subjective and anecdotal, and the experiment would be difficult for other researchers to reproduce.

One of the most abused prisoners, #416, and the guard known as "John Wayne", who was one of the most abusive guards, confront each other in an "encounter session" two months later.

Some of the experiment's critics argued that participants based their behaviour on how they were expected to behave, or modelled it after stereotypes they already had about the behaviour of prisoners and guards. In other words, the participants were merely engaging in role-playing. Another problem with the experiment was certain guards, such as "John Wayne", changed their behaviour because of wanting to conform to the behaviour that they thought Zimbardo was trying to elicit. In response, Zimbardo claimed that even if there was role-playing initially, participants internalized these roles as the experiment continued.

Additionally, it was criticized on the basis of ecological validity. Many of the conditions imposed in the experiment were arbitrary and may not have correlated with actual prison conditions, including blindfolding incoming "prisoners", not allowing them to wear underwear, not allowing them to look out of windows and not allowing them to use their names. Zimbardo argued that prison is a confusing and dehumanizing experience and that it was necessary to enact these procedures to put the "prisoners" in the proper frame of mind; however, it is difficult to know how similar the effects were to an actual prison, and the experiment's methods would be difficult to reproduce exactly so that others could test them.

Some said that the study was too deterministic: reports described significant differences in the cruelty of the guards, the worst of whom came to be nicknamed "John Wayne." (This guard alleges he started the escalation of events between "guards" and "prisoners" after he began to emulate a character from the Paul Newman film Cool Hand Luke. He further intensified his actions because he was nicknamed "John Wayne" though he was trying to mimic actor Strother Martin who played the role of the sadistic "Captain" in the movie.^[3]) Other guards were kinder and often did favours for prisoners. Zimbardo made no attempt to explain or account for these differences.

Also, it has been argued that selection bias may have played a role in the results. Researchers from Western Kentucky University recruited students for a study using an advertisement similar to the one used in the Stanford Prison Experiment, with and without the words "prison life." It was found that students volunteering for a prison life study possessed dispositions toward abusive behavior.

Lastly, the sample size was very small, with only 24 participants taking part over a relatively short period of time. This reality means that it is difficult to generalise across a wider scale. Also, the sample selection only contained males, meaning that the sample then is 'androcentric' again, leading to a lack of representativeness.

[edit] Haslam and Reicher

Alex Haslam and Steve Reicher (2003), psychologists from the University of Exeter and University of St Andrews, conducted a partial replication of the experiment with the assistance of the BBC, who broadcast scenes from the study as a reality TV program called The Experiment. Their results and conclusions differed from Zimbardo's and led to a number of publications on tyranny, stress and leadership (moreover, unlike results from the SPE, these were published in leading academic journals; e.g., British Journal of Social Psychology, Journal of Applied Psychology, Social Psychology Quarterly). While their procedure was not a direct replication of Zimbardo's, their study does cast further doubt on the generality of his conclusions. Specifically, it questions the notion that people slip mindlessly into role and the idea that the dynamics of evil are in any way banal. Their research also points to the importance of leadership in the emergence of tyranny (of the form displayed by Zimbardo when briefing guards in the Stanford experiment).^[4]

[edit] Comparisons to Abu Ghraib

When the Abu Ghraib military prisoner torture and abuse scandal was published in March 2004, many observers immediately were struck by its similarities to the Stanford Prison experiment — among them, Philip Zimbardo, who paid close attention to the details of the story. He was dismayed by official military and government efforts shifting the blame for the torture and abuses in the Abu Ghraib American military prison on to "a few bad apples" rather than acknowledging it as possibly systemic problems of a formally established military incarceration system.

Eventually, Zimbardo became involved with the defense team of lawyers representing Abu Ghraib prison guard Staff Sergeant Ivan "Chip" Frederick. He had full access to all investigation and background reports, testifying as an expert witness in SSG Frederick's court martial, resulting in an eight-year prison sentence for Frederick in October 2004.

Zimbardo drew on his knowledge gained from participating in SSG Frederick's case to write The Lucifer Effect: Understanding How Good People Turn Evil, (Random House, 2007), dealing with the many alleged connections between the Stanford Prison Experiment and the Abu Ghraib abuses.^[2]

[edit] Similar incidents

In April 2007, it was reported^[5] that high-school students in Waxahachie, Texas who were participating in a role-playing exercise fell into a similar abusive pattern of behaviour as exhibited in the original experiment.

In 2002, as mentioned above, the BBC conducted a similar experiment in The Experiment.

[edit] In Multimedia

In 1992, a documentary about the experiment was made available via the Stanford Prison Experiment website. The documentary, Quiet Rage: The Stanford Prison Experiment, was written by Zimbardo and directed and produced by Ken Musen.^[6]

A film about the experiment, entitled The Stanford Prison Experiment, is currently in production by Maverick Films. It was written by Christopher McQuarrie and Tim Talbott is said to feature actors Channing Tatum, Paul Dano, Ryan Phillippe, Giovanni Ribisi, Benjamin McKenzie, Charlie Hunnam, Kieran Culkin, Jesse Eisenberg, and Dylan Purcell, and is slotted for release in 2009.

[edit] See also

• Das Experiment, a 2001 film inspired by the Stanford events.
• The Third Wave, a 1967 recreation of Nazi Germany by high school teacher Ron Jones
  • The Wave, a novel by Todd Strasser based on the incident
  • The Wave, a short film based on the incident
• Milgram experiment on obedience to authority
• Peer pressure
• Lord of the Flies, a 1954 novel by William Golding, in which a group of youths degrade into dictatorship
• The Dispossessed, a 1974 novel by Ursula K. Le Guin, in which the protagonist Shevek took the part of a jail guard in a childhood game with very similar conditions and outcome.
• The Tipping Point: How Little Things Can Make a Big Difference, a book by Malcolm Gladwell, addresses this experiment.
• Abu Ghraib torture and prisoner abuse
• My Big Fat Greek Rush Week, an episode of the Veronica Mars television series depicting an experiment modeled on the Stanford Prison Experiment.
• When I Was Ming the Merciless a science fiction short story by Gene Wolfe, discusses an experiment similar to the Stanford Prison Experiment.

[edit] Footnotes

[edit] References

• Carnahan, C. & McFarland, S. (2007). Revisiting the Stanford Prison Experiment: Could Participant Self-Selection Have Led to the Cruelty? Personality and Social Psychology Bulletin, Vol. 33, No. 5, 603-614.
• Haney, C., Banks, W. C., & Zimbardo, P. G. (1973). Study of prisoners and guards in a simulated prison. Naval Research Reviews, 9, 1–17. Washington, DC: Office of Naval Research
• Haney, C., Banks, W. C., & Zimbardo, P. G. (1973). Interpersonal dynamics in a simulated prison. International Journal of Criminology and Penology, 1, 69–97.
• Haslam, S. Alexander & Reicher, Stephen (2003). Beyond Stanford: Questioning a role-based explanation of tyranny. Dialogue (Bulletin of the Society for Personality and Social Psychology), 18, 22–25.
• Musen, K. & Zimbardo, P. G. (1991). Quiet rage: The Stanford prison study. Videorecording. Stanford, CA: Psychology Dept., Stanford University.
• Reicher, Stephen., & Haslam, S. Alexander. (2006). Rethinking the psychology of tyranny: The BBC Prison Study. British Journal of Social Psychology, 45, 1–40.
• Zimbardo, P. G. (1971). The power and pathology of imprisonment. Congressional Record. (Serial No. 15, 1971-10-25). Hearings before Subcommittee No. 3, of the Committee on the Judiciary, House of Representatives, Ninety-Second Congress, First Session on Corrections, Part II, Prisons, Prison Reform and Prisoner's Rights: California. Washington, DC: U.S. Government Printing Office.
• Zimbardo, P. G (2007) [1] "Understanding How Good People Turn Evil". Interview transcript. "Democracy Now!", March 30, 2007. Accessed March 31, 2007

[edit] External links

• Official Site
• Homepage of Philip Zimbardo
• Summary of the experiment
• Zimbardo, P. (2007). From Heavens to Hells to Heroes. In-Mind Magazine.
• Fromm's criticism of the experiment
• The Experiment (IMDB) — German movie (Das Experiment) from 2001 inspired by the Stanford Experiment
• The Lie of the Stanford Prison Experiment — Criticism from Carlo Prescott, ex-con and consultant/assistant for the experiment
• The Artificial Prison of the Human Mind Article with Comments.
• Philip Zimbardo on Democracy Now! March 30 2007
• Philip Zimbardo on The Daily Show, March, 2007

Abu Ghraib and the experiment:

• BBC News: Is it in anyone to abuse a captive?
• BBC News: Why everyone's not a torturer
• Ronald Hilton: US soldiers' bad behavior and Stanford Prison Experiment
• Slate.com: Situationist Ethics: The Stanford Prison Experiment doesn't explain Abu Ghraib, by William Saletan
• IMDB: Untitled Stanford Prison Experiment Project
• VIDEO: Talk to MIT re: new book: The Lucifer Effect