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Preparation -

Dr. Zimbardo and his team converted the basement of the Stanford psychology building into a mock prison. This would be the setting for their experiment.

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Preparation -

They put an ad in the newspaper looking for paid volunteers to take part in a study on the psychological effects of prison life. They received 75 responses.

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Equal footing -

The chosen participants were all healthy young men from similar socio-economic backgrounds and with a good level of intelligence.

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Division -

They were randomly split into two groups: 10 prisoners and 11 guards.

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Arrest -

The experiment began with the prisoners being 'arrested' at their homes by real local police. They were taken to the police station and followed all of the procedures of a real arrest.

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The prisoners - They were then blindfolded and driven to the mock prison. The walls were bare and the doors and windows barred.

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The prisoners - The prisoners were all stripped and deloused. They were then given smocks to wear and assigned an ID number.

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Dehumanization -

They would only be referred to by their ID number going forward, and also had to refer to themselves and other prisoners by ID numbers instead of names.

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Disconnection -

The guards all wore identical uniforms and dark sunglasses to prevent eye contact.

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Replication -

These details were chosen to produce the feelings of humiliation and anonymity experienced by real prisoners, even though they do not represent real prison policies.

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The guards -

The guards worked eight hour shifts, three at a time. They had whistles and billy clubs and were told to do whatever was necessary to maintain order.

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Minimal interference -

Dr. Zimbardo acted as warden, but mainly sat back to watch events unfold.

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Counts -

The guards began to assert their dominance through 'counts.' They woke the prisoners up with whistles at 2:30 am and made them stand against the wall. This would be repeated at regular intervals to give the guards frequent opportunities for interaction with the prisoners.

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Punishments begin -

If the guards felt the prisoners were being disrespectful, they made them do push-ups, sometimes with a guard or fellow prisoner standing on their backs.

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Mounting intimidation -

The prisoners were forced to do meaningless tasks and were frequently insulted and demoralized by the guards.

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Waning defiance -

The prisoners were generally submissive and took the rules very seriously. They would even express anger towards fellow prisoners who broke the rules and sometimes sided with the guards.

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Rebellion - It was a surprise when the prisoners rebelled on the second day. They took off their smocks and barricaded themselves in their cells by pushing the beds against the door, taunting the guards through the bars.

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Guard response -

The guards were angry and frustrated, and decided to call in reinforcements. Off-duty guards were called in and they sprayed the prisoners with fire extinguishers before breaking down the doors.

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Aftermath -

The relationships between the guards and prisoners changed after this point. The guards became more derisive and openly contemptuous of the prisoners, and the prisoners became more submissive and down-trodden.

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Change in tactics - This was the point when the guards came up with the idea of using psychological tactics instead of physical ones.

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Privileges -

They began treating the prisoners' basic rights such as eating, brushing their teeth, or using the bathroom as 'privileges,' which could be given or taken away depending on their behavior.

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Humiliation -

They forced the prisoners to use a bucket as a toilet and refused to let them empty it, further adding to the degradation and harassment.

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Manipulation - The ringleaders of the rebellion had their privileges taken away, while the others were allowed to eat special food in front of them. This killed the solidarity between the prisoners.

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Manipulation -

Later on, they suddenly switched the roles and gave badly behaved prisoners privileges. This created the impression that they were being rewarded for informing on their fellow prisoners, even though this wasn't the case.

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Starting to crack -

When one prisoner had a mental breakdown and was taken out of the prison to rest in a room nearby, the guards made the remaining prisoners chant loudly that he was a 'bad prisoner.'

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Starting to crack -

Dr. Zimbardo urged the distressed man to quit the experiment but he refused, saying he couldn't leave because his cellmates thought badly of him.

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Loss of reality -

The doctor had to remind him that he was not a prisoner and that he was not in a real prison. The man who had been crying uncontrollably suddenly changed his demeanor and agreed to leave.

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The end -

Multiple prisoners had similar breakdowns where they began crying and screaming. The experiment was supposed to run for two weeks, but Dr. Zimbardo ended it on the sixth day.

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Conclusions -

The sadism and aggression that the guards displayed within a matter of days was shocking to Dr. Zimbardo and his team. The escalation of the abuse and psychological distress of the prisoners was unprecedented.

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Conclusions -

The researchers spotted several similarities between the behavior of the guards and the reported behavior of Nazi officers who guarded concentration camps.

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Conclusions -

Dr. Zimbardo drew the conclusion that human beings readily conform to social roles they are expected to play, particularly roles that are strongly stereotyped like that of a prison guard.

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Conclusions -

If we apply the findings of this experiment to other situations, it may help us to understand the growing epidemic of police brutality.

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Conclusions -

This experiment, along with many other events in history, show how susceptible ordinary people are to the power of situations and systems.

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Conclusions - It's scary to think that we are not entirely in control of ourselves. A greater awareness of our potential to be influenced in this manner can help us all to stay on track.

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Conclusions -

The real lesson learned from this experiment and escalating police brutality may be that there is an urgent need for reform within the criminal justice system.

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See also -

Follow this link to find out how racial bias works and how it's impacting the criminal justice system.

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