Stanford Prison Experiment – Prisoner Or Guard

The Stanford prison experiment (SPE) was a study of the the psychological effects of becoming a prisoner or prison guard. The experiment was conducted at Stanford University in 1971, by a team of researchers led by psychology professor Philip Zimbardo using college students.

It was funded by the U.S. Office of Naval Research and was of interest to both the U.S. Navy and Marine Corps as an investigation into the causes of conflict between military guards and prisoners. The experiment is a classic study on the psychology of imprisonment and is a topic covered in most introductory psychology textbooks.

The participants adapted to their roles well beyond Zimbardo’s expectations, as the guards enforced authoritarian measures and ultimately subjected some of the prisoners to psychological torture. Many of the prisoners passively accepted psychological abuse and, at the request of the guards, readily harassed other prisoners who attempted to prevent it.

The experiment even affected Zimbardo himself, who, in his role as the superintendent, permitted the abuse to continue. Two of the prisoners quit the experiment early, and the entire experiment was abruptly stopped after only six days, to an extent because of the objections of graduate student Christina Maslach, whom Zimbardo was dating (and later married).

GOALS AND METHODS

Zimbardo and his team aimed to test the hypothesis that the inherent personality traits of prisoners and guards are the chief cause of abusive behavior in prison. Participants were recruited and told they would participate in a two-week prison simulation.

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 of the middle class.

The group was intentionally selected to exclude those with criminal backgrounds, psychological impairments, or medical problems. They all agreed to participate in a 7- to 14-day period and received $15 per day.

The experiment was conducted in the basement of Jordan Hall (Stanford’s psychology building). 12 of the 24 participants were assigned the role of prisoner (9 plus 3 alternates), while the other 12 were assigned the role of guard (also 9 plus 3 alternates).

Zimbardo took on the role of the superintendent, and an undergraduate research assistant the role of the warden. Zimbardo designed the experiment in order to induce disorientation, depersonalization, and deindividualization in the participants.

The researchers held an orientation session for guards the day before the experiment, during which guards were instructed not to physically harm the prisoners or withhold food or drink.

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EXPERIMENT SET-UP

The researchers provided the guards with wooden batons to establish their status, clothing similar to that of an actual prison guard, and mirrored sunglasses to prevent eye contact.

Prisoners wore uncomfortable, ill-fitting smocks and stocking caps, as well as a chain around one ankle. Guards were instructed to call prisoners by their assigned numbers, sewn on their uniforms, instead of by name.

The 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 included fingerprinting and taking mug shots.

The prisoners were transported to the mock prison from the police station, where they were strip searched and given their new identities.

The small mock prison cells were set up to hold three prisoners each. There was a small corridor for the prison yard, a closet for solitary confinement, and a bigger room across from the prisoners for the guards and warden.

After a relatively uneventful first day, on the second day the prisoners in Cell 1 blockaded their cell door with their beds and took off their stocking caps, refusing to come out or follow the guards’ instructions.

ASSIGNED NUMBERS

Guards forced the prisoners to repeat their assigned numbers to reinforce the idea that this was their new identity. Guards soon used these prisoner counts to harass the prisoners, using physical punishment such as protracted exercise for errors in the prisoner count.

Sanitary conditions declined rapidly, exacerbated by the guards’ refusal to allow some prisoners to urinate or defecate anywhere but in a bucket placed in their cell. As punishment, the guards would not let the prisoners empty the sanitation bucket.

Mattresses were a valued item in the prison, so the guards would punish prisoners by removing their mattresses, leaving them to sleep on concrete. Some prisoners were forced to be naked as a method of degradation. Several guards became increasingly cruel as the experiment continued; experimenters

Zimbardo argued that the prisoners had internalized their roles, since some had stated they would accept “parole” even if it would mean forfeiting their pay, despite the fact that quitting would have achieved the same result without the delay involved in waiting for their parole requests to be granted or denied.

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ABORTED EXPERIMENT

Zimbardo aborted the experiment early when Christina Maslach, a graduate student in psychology whom he was dating (and later married), objected to the conditions of the prison after she was introduced to the experiment to conduct interviews.

On August 20, 1971, Zimbardo announced the end of the experiment to the participants.

The results of the experiment favor situational attribution of behavior rather than dispositional attribution (a result caused by internal characteristics). In other words, it seemed that the situation, rather than their individual personalities, caused the participants’ behavior.

Participants’ behavior was modified due to the fact that they were watched as opposed to a lurking variable (Hawthorne effect). Even knowing they were being observed, guards and prisoners acted differently than normal. Guards felt the need to show their dominance even

Prisoners were being disrespected by the guards in many ways. Prisoners were being referred to by number instead of their real name. It dehumanized the prisoners, which resulted in a loss of personal identity. With no control, prisoners learned they had little effect on what happened to them, ultimately causing them to stop responding.

SADISTIC

The guards and prisoners adapted to their roles more than Zimbardo expected, stepping beyond predicted boundaries, 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; five of them had to be removed from the experiment early.

After Maslach confronted Zimbardo and forced him to realize that he had been passively allowing unethical acts to be performed under his supervision, Zimbardo concluded that both prisoners and guards had become grossly absorbed in their roles.

Because of the nature and questionable ethics of the experiment, Zimbardo found it impossible to keep traditional scientific controls in place. He was unable to remain a neutral observer, since he influenced the direction of the experiment as the prison’s superintendent.

Conclusions and observations drawn by the experimenters were largely subjective and anecdotal, and the experiment is practically impossible for other researchers to accurately reproduce.

“John Wayne” (the real-life Dave Eshelman), one of the guards in the experiment, said the study placed undue emphasis on the cruelty of the guards, and that he caused the escalation of events between guards and prisoners after he began to emulate a character from the Paul Newman film Cool Hand Luke (1967).

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PERSONA

The study has been criticized for demand characteristics by psychologist Peter Gray. He argues that participants in psychological experiments are more likely to do what they believe the researchers want them to do. The guards were essentially told to be cruel.

Most of the Stanford guards did not exhibit any cruel or unusual behavior, often being friendly and doing favors for the prisoners…The statistical validity of the sample of participants, 24 male Stanford students of about the same age, has been called into question as being too small and restrictive to be generally applicable to the population at large.

Guards and prisoners were playing the role of their authority, which is subjective. They may have not acted the same in real life situations. In particular, the environment and authority roles they found themselves in changed their actions.

When acts of prisoner torture and abuse at the Abu Ghraib prison in Iraq were publicized in March 2004, Zimbardo himself, who paid close attention to the details of the story, was struck by the similarity with his own experiment.

Eventually, Zimbardo became involved with the defense team of lawyers representing one of the Abu Ghraib prison guards, Staff Sergeant Ivan “Chip” Frederick. He was granted full access to all investigation and background reports, and testified as an expert witness.

ETHICAL ISSUES

The experiment presented several ethical issues, the most serious of which was that the experiment continued even when participants did not wish to continue. Despite the fact that participants were told they had the right to leave at any time, Zimbardo did not allow this during the experiment.

Currently, there are ethical guidelines to be followed. The Stanford Prison Experiment led to the implementation of rules to preclude any harmful treatment of participants. Before they’re implemented, human studies must now undergo an extensive review by an institutional review board (US) or ethics committee (UK).

A post-experimental debriefing is now considered an important ethical consideration to ensure that participants are not harmed in any way by their experience in an experiment. Though Zimbardo did conduct debriefing sessions, they were several years after the Stanford Prison Experiment.

Psychologists Alex Haslam and Steve Reicher conducted the BBC Prison Study in 2002 and was published in 2006. This was a partial replication of the Stanford prison experiment, which broadcast events in the study in a documentary series called The Experiment.

While Haslam and Reicher’s procedure was not a direct replication of Zimbardo’s, their study casts 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 automatic.

The Stanford prison experiment was in part a response to the Milgram experiment at Yale beginning in 1961 and published in 1963.

In the Milgram and the Zimbardo study participants comply to social pressures. Conformity is strengthened by allowing some participants to feel more or less powerful than others.