The most dramatic evidence of the impact of the mock prison upon the participants was seen in the gross reactions of five prisoners who had to be released from the study because of extreme emotional depression, crying, rage, or acute anxiety. The pattern of symptoms was quite similar in four of the subjects and began as early as the second day of imprisonment. The fifth subject was released after being treated for a psychosomatic rash which covered portions of his body. Of the remaining prisoners, only two said they were unwilling to forfeit all the money they had earned in return for being “paroled” from the study. When the experiment was terminated prematurely after only six days, all the remaining prisoners were delighted by their unexpected good fortune; in contrast, most of the guards seemed to be distressed by the decision to stop the experiment. It appeared to us that the guards had become sufficiently involved in their roles so that they now enjoyed the extreme control and power they exercised and were reluctant to give it up. One guard, who did report being personally upset at the suffering of the prisoners, claimed to have considered asking to change his role to become one of them—but never did so. None of the guards ever failed to come to work on time for their shift, and indeed, on several occasions guards remained on duty voluntarily and uncomplainingly for extra hours—without additional pay.
The extreme reactions which emerged in both groups of subjects provide clear evidence of the power of the social forces operating in this pathological setting. There were, however, individual differences observed in styles of coping with this stressful experience, as well as varying degrees of success in adaptation to it. While all were somewhat adversely affected by it, half the prisoners did “endure” the oppressive atmosphere—at least in the sense that they remained until the study was completed. Not all of the guards resorted to the overt and inventive forms of hostility employed by others. Some guards were tough but fair (“played by the rules”), some went far beyond their roles to engage in cruelty and harassment, while a few were passive and rarely instigated any coercive control over the prisoners. It is important to emphasize, however, that at some time during the six days all guards participated in what could be characterized as sadistic treatment of prisoners….
Representative Personal Statements
Much of the flavor and impact of this prison experience has been unavoidably lost in the relatively formal, objective analyses outlined in [other papers]. The following quotations taken from interviews, conversations, and questionnaires provide a more personal view of what it was like to be a prisoner or guard in the “Stanford County Prison” experiment.
Guards’ Comments
They [the prisoners] seemed to lose touch with the reality of the experiment—
they took me so seriously. I didn’t interfere with any of the guards’ actions. Usually if what they were doing bothered me, I would walk out and take another duty…. looking back, I am impressed by how little I felt for them.
They [the prisoners] didn’t see it as an experiment. It was real and they were fighting to keep their identity. But we were always there to show them just who was boss.
I was tired of seeing the prisoners in their rags and smelling the strong odors of their bodies that filled the cells. I watched them tear at each other, on orders given by us.
Acting authoritatively can be fun. Power can be a great pleasure. During the inspection, I went to cell 2 to mess up a bed which the prisoner had made and he grabbed me, screaming that he had just made it, and he wasn’t going to let me mess it up. He grabbed my throat, and although he was laughing I was pretty scared. I lashed out with my stick and hit him in the chin (although not very hard) and when I freed myself I became angry.
Prisoners’ Comments
The way we were made to degrade ourselves really brought us down, and that’s why we all sat docile toward the end of the experiment. I realize now (after it’s over) that no matter how together I thought I was inside my head, my prison behavior was often less under my control than I realized. No matter how open, friendly, and helpful I was with other prisoners I was still operating as an isolated, self-centered person, being rational rather than compassionate.
I began to feel I was losing my identity, that the person I call _______, the person who volunteered to get me into this prison (because it was a prison to me, it still is a prison to me, I don’t regard it as an experiment or a simulation …) was distant from me, was remote until finally I wasn’t that person, I was 416. I was really my number and 416 was really going to have to decide what to do.
I learned that people can easily forget that others are human.
Debriefing Encounter Sessions
Because of the unexpectedly intense reactions (such as the above) generated by this mock prison experience, we decided to terminate the study at the end of six days rather than continue for the second week. Three separate encounter sessions were held, first for the prisoners, then for the guards, and finally for all participants together. Subjects and staff openly discussed their reactions, and strong feelings were expressed and shared. We analyzed the moral conflicts posed by this experience and used the debriefing sessions to make explicit alternative courses of action that would lead to more moral behavior in future comparable situations.
Follow-ups on each subject over the year following termination of the study revealed that the negative effects of participation had been temporary, while the personal gain to the subjects endured.
Conclusions and Discussion
It should be apparent that the elaborate procedures (and staging) employed by the experimenters to ensure a high degree of “mundane realism” in this mock prison contributed to its effective functional simulation of the psychological dynamics operating in “real” prisons. We observed empirical relationships in the simulated prison environment which were strikingly isomorphic to the internal relations of real prisons, corroborating many of the documented reports of what occurs behind prison walls. Most dramatic and distressing to us were the ease with which sadistic behavior could be elicited from individuals who were not “sadistic types” and the frequency with which acute emotional breakdowns could occur in persons selected precisely for their emotional stability.
Author’s Notes
This research was funded by an ONR grant: N00014-67-A-0112-0041 to Professor Philip G. Zimbardo.
The ideas expressed in this paper are those of the authors and do not imply endorsement of ONR or any sponsoring agency. We wish to extend our thanks and appreciation for the contributions to this research by David Jaffe who served as “warden” and pretested some of the variables in the mock prison situation. In addition, Greg White provided invaluable assistance during the data reduction phase of this study. Many others (most notably Carolyn Burkhart, Susie Phillips, and Kathy Rosenfeld) helped at various stages of the experiment, with the construction of the prison, prisoner arrest, interviewing, testing, and data analysis—we extend our sincere thanks to each of these collaborators. Finally, we especially wish to thank Carlo Prescott, our prison consultant, whose personal experience gave us invaluable insights into the nature of imprisonment.