Stanford Prison Experiment: http://www.prisonexp.org./

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The Stanford Prison Experiment examined the psychological effects of imprisonment. Eighteen male participants were randomly assigned to the role of “guard” or “prisoner” in a simulated prison environment. As part of the experiment, prisoners were dehumanized through strip searches, forced wearing of ward dresses, and assignment of numbers instead of names. Guards were given uniforms and sunglasses to provide anonymity and they were given power over the prisoners. Over the course of the experiment, the prisoners experienced negative psychological consequences including helplessness, loss of identity, emotional disturbance, and extreme distress. Guards displayed increasingly harassing and sadistic behaviors toward the prisoners. Even the principle investigator psychologically adapted to the role of “superintendent” and exerted power over the prisoners. The two-week experiment ended after only six days due to its detrimental effects on all participants.

This study is considered a classic in social psychology because it reveals how environments, roles, and power relationships can influence the behaviors of ‘ordinary’ people in ways that lead to harmful consequences. The implications of the study relate directly to instances across history including Nazi imprisonment camps, American correctional facilities, and the torture of Iraqi prisoners by U.S. soldiers.