It has been forty years since the Stanford prison experiment. This classic psychology study simulated prison life in the basement of a Stanford psychology building. The study randomly separated student volunteers to be either prison guards or inmates.
The study was supposed to last two weeks. However, it ended after only six days, due to how the situation affected the college students who participated. In only a few days, guards became sadistic and prisoners became depressed and showed signs of extreme stress. (A more detailed summary of the study is here.)
For decades, this experiment has been one of psychology’s most famous studies. It has been long heralded as a scientific explanation for how people are influenced to behave based on their circumstances. However, more recent evidence suggests that the experiment was more likely an example of poor research methods.
In 2019, the journal American Psychologist published a thorough debunking of the experiment. For example, the students assigned to be guards were reportedly trained to act a certain way. Also, there is evidence that the conclusions of the experiment were predetermined.
Edited in 2022: The Stanford Prison Experiment has since been the subject of a film by Kyle Patrick Alvarez.