The Stanford Prison Experiment was a research study conducted during 1971 as a means of analyzing the human response to captivity. Headed by a researchers led by Philip Zimbardo, the Stanford Prison Experiment involved the participation of undergraduate students who played the roles of both guards and prisoners in a mock prison that was set up in the basement of the psychology building on the Stanford University campus. As best as possible, the study sought to recreate real life conditions found in prisons of the era, and the impact that those conditions had on the behavior patterns of both persons in positions of power and those who were under the direct control of the established authorities.
As life in the mock Stanford prison began to fall into patterns, the participants began to exhibit certain tendencies that were directly related to their assigned positions within the experiment. The undergraduate students who were filling the roles of guards in the experiment incrementally began to exhibit the tendency to treat those who were functioning as prisoners as of lesser worth. Bonding occurred among the guards, setting them as a group against the prisoners. As a result, there were instances in which several of the guards exhibited tendencies to abuse the authority granted under the terms of the experiment. The abuse was so severe that it was necessary to release several volunteers from the experiment before the project was completed.
The prisoners also began to identify more closely with one another, both as a group and as a collection of sub groups within the community. To a degree, the impact of social, economic, and racial diversity was excluded from the experiment, as the volunteers selected for the Stanford Prison Experiment were overwhelmingly Caucasian and from middle class backgrounds. In spite of the limited cross section of participants in the experiment, both the guards and the prisoners tended to confirm certain assumptions about disposition and identification characteristics that emerge in places of confinement. The research team was careful to not share these assumptions with the test subjects in advance, so that there would not be any outside influence from the team that would indicate to the volunteers what constituted proper role behavior.
Conditions within the experiment deteriorated at an alarming rate, which led to the Stanford Prison Experiment being shut down after only six days. Exhibitions of sadistic behavior, humiliating tactics aimed at the prisoners, and choices designed to challenge individuals to choose between the good of the community and the good of the individual were common. Still, Zimbardo considered the experiment to be successful in terms of advancing the understanding of social psychology in a forced environment.
Over the years, a number of criticisms of the Stanford Prison Experiment have been included in various studies and scholarly works. Charges that the structure of the experiment led to conclusions that were subjective and unscientific in many cases have been common, although the experiment does continue to have the support of a few social psychologists.