The Stanford Prison Experiment is one of history’s most famous and fascinating psychological studies. Although it took place more than 40 years ago, it continues to be influential to this day.
With results that shocked even the researchers themselves, the Experiment provoked discussion, replications and critique as well as a book, movie and documentaries.
What Was the Experiment?
It was 1971, Northern California at Stanford University, one of America’s most prestigious schools of learning.
Twenty-one participants were selected: all young men who were physically fit and healthy, with no record of anti-social behaviour.
The subjects were randomly assigned roles of ‘prisoner’ or ‘guard’, and paid $15 per day.
The ‘guards’ were told to prevent escape and maintain a necessary degree of order in the makeshift prison, which was constructed in the Stanford University’s basement. Physical aggression and abuse were forbidden; but apart from this, there were no policies or rules.
The aim was to observe the impact of the environment on the behaviour, interaction and emotions of those involved – how would participants react to an oppressive regime? Would the ‘prisoners’ submit or rebel? Would the guards – normal, everyday people – become corrupted by their positions of power?
After just six days, the experiment was terminated because it became ethically unacceptable.
The transformation, both of the prisoners and guards, was remarkable. The guards referred to prisoners by their numbers only, deprived them of sleep and forced them to undertake humiliating tasks, such as cleaning toilets with their bare hands.
Prisoners were degraded, mocked and made to march in line with bags over their heads, and in chains for toilet trips. While some guards never actively participated in tormenting the prisoners, they also never challenged those who did. And significantly, the behaviour amongst prisoners changed – there was no solidarity, and it was difficult for those being abused to stand up for themselves.
By the sixth day, four participants had broken down and were released. As the author of the Experiment, Professor Zimbardo, put it:
“How we went about testing these questions and what we found may astound you. Our planned two-week investigation into the psychology of prison life had to be ended after only six days because of what the situation was doing to the college students who participated. In only a few days, our guards became sadistic and our prisoners became depressed and showed signs of extreme stress.”
After the Experiment, all participants met with Zimbardo to discuss the experience. One of the ‘prisoners’ said “it let me in on some knowledge that I’ve never experienced firsthand. Because I know what you can turn in to, I know what you’re willing to do.”
What Have We Learnt?
The Experiment hits at the core of whether humans are inherently good or evil, or whether it depends on their situation.
The study found that seemingly ‘normal’ people could become sadistic tyrants if given enough power and not held accountable for their misdeeds– and the ‘transformation’ occurred within a remarkably short period of time.
Zimbardo used the study to explain the horrific actions committed by thousands of ‘normal’ people during the Holocaust in Germany – as well as the torture, humiliation and murder of Iraqis by Americans after 9/11, including in Abu Ghraib prison.
After the Experiment, guidelines and safeguards were implemented to ensure that participants in future psychological experiments could not be put at risk.
The study provides a fascinating insight into how and why abuse in prisons and other environments of extreme power disparity occurs, including in police stations and mental health facilities.
The Experiment makes it clear that strict rules and guidelines must be developed, monitored and implemented when it comes to such environments, and that those who engage in abuse must quickly be brought to account.