Standford Prison Experiment 

conducted by Philip Zimbardo



Known as the “Stanford Prison Experiment”, the aim of this experiment was to investigate the psychological effects of turning someone into a prisoner or a guard, observing how the prison institution influences the behaviour of its inmates.

Twenty-four volunteer male students were selected and randomly assigned a prisoner or guard character to spend two weeks in a simulated jail in the basement of the Stanford School of Psychology.

As days went by, an overwhelming atmosphere took over the situation. Using different techniques, the inmates were forced to abandon their identities and were constantly humiliated. They developed some pathological behaviours while some guards started to have sadistic conducts, denigrating and abusing the inmates in many ways. 

After only six days, several moral questionable situations were noticed, which led to the simulation being cancelled.  

The Stanford Prison Experiment was carried out by a team of researchers led by Philip Zimbardo of the Stanford University in 1971. Font: prisonexp.org

01


Ad for Participants, Stanford Experiment, 1971.

Copyright free image, taken from prisonexp.org.

02


Stanford County Prison, Stanford Experiment, 1971.
Copyright free image, taken from prisonexp.org.

03


Handcuffing Prisoner #8612, Stanford Experiment, 1971.

Copyright free image, taken from prisonexp.org.


04


Meeting with the Superintendent, Stanford Experiment, 1971.

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05


Prisoners Facing the Wall and Doing Push-ups, Stanford Experiment, 1971.

Copyright free image, taken from prisonexp.org.


06


Prisoner Against Wall, Stanford Experiment, 1971.

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07


Prisoner Sleeping, Stanford Experiment, 1971.

Copyright free image, taken from prisonexp.org.

08


Filming the Experiment, Stanford Experiment, 1971.

Copyright free image, taken from prisonexp.org.