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Abu Ghraib: Lessons from behavioural finance and for corporate governance

Zimbardo’s prison experiment [3]

The events in Abu Ghraib and other prisons were actually sadly predictable (of course, all the more so with hindsight). In 1971, Philip Zimbardo[4] designed an experiment that has eerie parallels with events of late. Zimbardo and his colleagues literally built a prison under the psychology department of Stanford University. The experimenters selected 22 subjects to participate in the prison environment. The 22 were selected from an initial pool of 75.

The chosen 22 were judged to be the most stable, both mentally and physically, the most mature, and the least involved in anti-social behaviour. They were, to all intents and purposes, the most ‘normal’ of the potential candidates. The resulting group predominately consisted of middle class Caucasians. They were unknown to each other. All participants were paid $15 per day. On a random basis, half the subjects were assigned to the role of guards, and half to the role of prisoners.

The ‘prisoners’ were to remain in the prison for 24 hours a day for the duration of the experiment. The ‘guards’ worked on three-man, eight hour shifts, going about their usual lives at other times. The ‘guards’ were briefed on the day before the arrival of the ‘prisoners’. Their instruction was simple “maintain a reasonable degree of order within the prison necessary for its effective functioning”. The specifics of how this was to be achieved were left to the discretion of the guards. An explicit prohibition against the use of physical punishment or aggression was given.

The guards wore khaki shirts and trousers, carried a whistle and a nightstick, and were told to wear reflecting sunglasses. The prisoners had a somewhat rougher time. The police ‘arrested’ each of the prisoners at their residences. They were charged with either armed robbery or burglary, read their rights, and handcuffed, and taken to the police station. At the station, each was fingerprinted and photographed just like any other suspect. They were then blindfolded and taken to the mock prison. On arrival, the prisoners were stripped, sprayed with a delousing liquid, left to stand naked alone for a while and then put into their new prison uniform.

These consisted of a loose fitting smock, with an id number on the front and back. Underwear was not allowed, a light lock and chain was placed on the ankle. The prisoners were to be served three bland meals per day, were allowed three supervised toilet visits, and given two hours of reading or letter writing per day. Work assignments were issued. Two visiting periods per week were scheduled. Three times a day the prisoners assembled for a roll call, during which they were tested on their id numbers and the rules of the prison. At first such roll calls lasted only around ten minutes. However, as the days progressed so these calls extended until some lasted several hours! Many of the pre-set features of the routine were modified or ignored by the guards, and many of the privileges (such as reading) were forgotten as time went on. The results of this experiment were dramatic to say the least.

Zimbardo et al note “guards and prisoners showed a marked tendency toward increased negativity of affect…prisoners expressed intentions to do harm to others more frequently…encounters became negative, hostile, and dehumanizing. Prisoners immediately adopted a generally passive response mode, while guards assumed a very active initiative role in all interactions.” The prisoners became zombie-like in obedience. Even trying to side with the guards against each other. The guards became sadists who seemed to enjoy dominating and humiliating the prisoners.

Zimbardo[5] recently noted the disturbingly similar outcomes of his prison experiment and events in Abu Ghraib. The similarities even extend to the sorts of humiliation inflicted by the guards on the prisoners! Zimbardo notes that in his ‘prison’ the guards forced the prisoners to engage in mock sodomy, a feature repeated in Abu Ghraib. The most dramatic evidence of the impact was seen in the extreme reactions of five prisoners. They had to be released because of extreme emotional depression, crying, rage and acute anxiety. The experiment was terminated after just six days!

As you read this, the chances are you are sitting saying to yourself, I would behave differently. After all, there was nothing to stop the guards and prisoners interacting in a pleasant fashion. They were simply put into an environment. The rules of which were largely flexible and endogenously determined. But remember, these were ordinary young men, fit, healthy and generally well adjusted. Also remember, the fundamental attribution error outlined at the very start of this note. Zimbardo’s work seems to offer massive support for a situational view of the world.


3 See www.prisonexp.org for a slide show and further details on this experiment

4 Haney, Banks and Zimbardo (1973) A study of prisoners and guards in a simulated prison, Naval Research Reviews

5 Zimbardo (2005) You can’t be a sweet cucumber in a vinegar barrel, Interview with Edge

By Dr James Montier

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