The Stanford Prison Experiment was designed to control for the individual personality variables that were often used at that time to explain behaviour in prison and other institutional settings. That is, the researchers neutralized the explanatory argument that pathological traits alone could account for extreme and abusive behaviour by 1) selecting a group of participants who were psychological healthy and who had scored in the normal range of the numerous personality variables they measured and selected for; and 2) by assigning participants to either the role of prisoner or guard on a completely random basis. The behaviour that resulted when these otherwise healthy, normal participants were placed in the extreme environment of a simulated prison would have to be explained largely, if not entirely, on the basis of the characteristics of the social setting or situation in which they had been placed.

The setting itself was designed to be as similar to an actual prison as possible. Constructed in the basement of the Psychology Department at Stanford University, the ‘Stanford County Prison’ had barred doors on the small rooms that served as cells; beds on which the prisoners slept; a hallway area that was converted to a prison ‘yard’ where group activities were conducted; and a small room that served as a short-term ‘solitary confinement’ cell that could be used for disciplining unruly prisoners. The prisoners wore uniforms that were designed to de-emphasize their individuality and to underscore their powerlessness. The guards, on the other hand, donned military-like garb, complete with reflecting sunglasses and nightsticks. The guards generated a set of rules and regulations that, in many ways, resembled those in operation in actual prisons, and the prisoners were expected to comply with their orders. However, the guards were instructed not to resort to physical force in order to gain prisoner compliance.

Despite the lack of any legal mandate for the ‘incarceration’ of the prisoners, and despite the fact that both groups were told that they had been randomly assigned to their roles (so that, for example, the guards knew that the prisoners had done nothing to ‘deserve’ their degraded prisoners status), the behaviour that ensued was remarkably similar to behaviour that takes place inside actual prisons and surprisingly extreme in intensity and effect. Thus, initial prisoner resistance and rebellion were met forcibly by the guards, who quickly struggled to regain their power and then proceeded to escalate their mistreatment of prisoners throughout the study, at the slightest sign of affront or disobedience. In some instances, the guards conspired to mistreat prisoners physically outside the presence of the experimenters and to leave prisoners in the solitary confinement cell beyond the one-hour limit the researchers had set.

Conversely, the prisoners resisted the guards’ orders at first but then succumbed to their superior power and control. Some prisoners had serious emotional breakdowns in the course of the study and had to be released; others became compliant and conforming, rarely if ever challenging the ‘authority’ of the guards. Despite the fact that the researchers could not keep the prisoners in the study against their will (and they had been informed at the outset of the study of their legal right to leave), as the study proceeded they ‘petitioned’ the prison ‘administrators’ for permission to be ‘paroled’ and they returned passively to their cells when their requests were denied. By the end of the study, they had disintegrated as a group. The guards, on the other hand, solidified and intensified their control. Although some of the guards were more extreme and inventive in the degradation they inflicted on the prisoners, and some were more passive and less involved, none of the guards intervened to restrain the behaviour of their more abusive colleagues. Although the study was designed to last for two full weeks, the extreme nature of the behaviour that occurred led the researchers to terminate it after only six days.

Controversial from the outset and widely discussed and cited since it was conducted, the study has come to stand in psychology and related disciplines as a demonstration of the power of situations – especially extreme institutional settings such as prisons – to shape and control the behaviour of the persons placed inside them. Its results give lie to the notion that extreme social behaviour can only – or even mostly – be explained by resorting to the extreme characteristics of the people who engage in it. The experiment counsels us to look instead to the characteristics of the settings or situations in which the behaviour occurs. It also stands as a challenge to what might be termed the ‘presumption of institutional rationality’ – that is, the tendency to assume that institutions operate on the basis of an inherent rationality that should be abided rather than questioned. Instead, the Stanford Prison Experiment (itself the most ‘irrational’ of prisons, in the sense that the guards had no legal authority over the prisoners who, in turn, had committed no crimes that warranted their punishment) suggests that a kind of ‘psychologic’ may operate in these settings that controls role-bound behaviour, whether or not that behaviour actually furthers legitimate goals.

Related entries

Order and control; Power; Prison officers; Security; Structure/agency (‘resistance’); Total institutions.