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Orientation session
During this session, the 12 guards were told that they were not permitted to physically harm the prisoners, but they could use various psychological methods to degrade and dehumanize the prisoners in order to instill a feeling of powerlessness to maintain law and order in the prison. -
Guard's Uniforms
All guards were dressed in identical uniforms of khaki, and they carried a whistle around their neck and a billy club borrowed from the police. Guards also wore special sun-glasses, Mirror sunglasses prevented anyone from seeing their eyes or reading their emotions. -
Period: to
Orientation
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Mass Arrest (continued)
The car arrived at the station, the suspect was brought inside, formally booked, again warned of his Miranda rights, finger printed, and a complete identification was made. Blindfolded and in a state of mild shock over their surprise arrest by the city police, prisoners were put into a car and driven to the "Stanford County Jail" for further processing. -
Prisoners' Uniform
The main part of this uniform was a dress, or smock, which each prisoner wore at all times with no underclothes. On the smock, in front and in back, was his prison ID number. On each prisoner's right ankle was a heavy chain, bolted on and worn at all times. Rubber sandals were the footwear, and each prisoner covered his hair with a stocking cap made from a woman's nylon stocking. -
Stanford County Jail
The prisoners were brought into the jail one at a time and greeted by the Warden, who conveyed the seriousness of their offense and their new status as prisoners. Each prisoner was systematically searched and stripped naked. He was then deloused with a spray, to convey the belief that he may have germs or lice. The experiment began with 9 guards and 9 prisoners in the jail. 3 guards worked 3 8- hour shifts each, while each of the 3 cells constantly contained 3 prisoners. -
Mass Arrest
On a quiet Sunday morning in August, a Palo Alto, California, police car swept through the town picking up 12 male college students as part of a mass arrest for violation of Penal Codes 211, Armed Robbery, and Burglary. The suspect was picked up at his home, charged, warned of his legal rights, spread-eagled against the police car, searched, and handcuffed. The suspect was then put in the rear of the police car and carried off to the police station, the sirens wailing. -
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Duration of Experiment
This is the actual duration of the experiment which was initally planned to last for 14 days instead of just 6 days. -
Asserting Authority
At 2:30 A.M. the prisoners were rudely awakened from sleep by blasting whistles for the first of many "counts." The counts served the purpose of familiarizing the prisoners with their numbers (counts took place several times each shift and often at night). But more importantly, these events provided a regular occasion for the guards to exercise control over the prisoners. Guards began using push-ups as a form of physical punishment when prisoners disobeyed their orders. -
Rebellion
The prisoners removed their stocking caps, ripped off their numbers, and barricaded themselves inside the cells by putting their beds against the door. The guards were very much angered and frustrated because the prisoners also began to taunt and curse them. When the morning shift of guards came on, they became upset at the night shift who, they felt, must have been too lenient. -
Special Privileges (continued)
After half a day of this treatment, the guards then took some of these "good" prisoners and put them into the "bad" cells, and took some of the "bad" prisoners and put them into the "good" cell, thoroughly confusing all the prisoners. Some of the prisoners who were the ringleaders now thought that the prisoners from the privileged cell must be informers, and suddenly, the prisoners became distrustful of each other. -
Effect of Rebellion
Going to the toilet became a privilege which a guard could grant or deny at his whim. After the nightly 10:00 P.M. lights out "lock-up," prisoners were often forced to urinate or defecate in a bucket that was left in their cell. On occasion the guards would not allow prisoners to empty these buckets. The guards were tough on the ringleader of the rebellion, Prisoner #5401. He was a heavy smoker, and they controlled him by regulating his opportunity to smoke. -
1st Prisoner Breakdown
Prisoner #8612 began suffering from acute emotional disturbance, disorganized thinking, uncontrollable crying, and rage. #8612 was given the offer of becoming an informant in exchange for no further guard harassment. Prisoner #8612 told other prisoners, "You can't leave. You can't quit." #8612 then began to act "crazy," to scream, to curse, to go into a rage that seemed out of control. He was then released. -
Handling the Rebellion
The guards first called in reinforcements, bringing in the three guards who were waiting at home on stand-by call. They got a fire extinguisher which shot a stream of skin-chilling carbon dioxide, and they forced the prisoners away from the doors. The guards broke into each cell, stripped the prisoners naked, took the beds out, forced the ringleaders of the prisoner rebellion into solitary confinement, and generally began to harass and intimidate the prisoners. -
Special Priveleges
One of the 3 cells was designated as a "privilege cell." The 3 prisoners least involved in the rebellion were given special privileges. They got their uniforms back, got their beds back, and were allowed to wash and brush their teeth. The others were not. Privileged prisoners also got to eat special food in the presence of the other prisoners who had temporarily lost the privilege of eating. The effect was to break the solidarity among prisoners. -
Visiting Hours
The experimenters had the prisoners washed, shaved, and groomed, had them clean their cells, fed them, and played music on the intercom. When friends and family came, the experimenters had them register, wait half an hour, and told them that only 2visitors could see any 1 prisoner, could only have 10 minutes of visiting time, and had to be under guard supervision during the visit.
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Effect of Escape Plot
The rumor of the prison break turned out to be just a rumor. The guards again escalated very noticeably their level of harassment, increasing the humiliation they made the prisoners suffer, forcing them to do menial, repetitive work such as cleaning out toilet bowls with their bare hands. The guards had prisoners do push-ups, jumping jacks, whatever the guards could think up, and they increased the length of the counts to several hours each. -
The Escape Plot
One of the guards overheard the prisoners talking about an escape that would take place immediately after visiting hours. Prisoner #8612, who was released the night before, was going to round up some friends and break in to free the prisoners. The plan was to dismantle our jail after the visitors left, call in more guards, chain the prisoners together, put bags over their heads, and transport them to a fifth floor storage room until after the anticipated break in. -
Evaluations by Catholic Priest
The chaplain interviewed each prisoner individually, and half the prisoners introduced themselves by number rather than name. After some small talk, he popped the key question: "Son, what are you doing to get out of here?" When the prisoners responded with puzzlement, he explained that the only way to get out of prison was with the help of a lawyer. He then volunteered to contact their parents to get legal aid if they wanted him to, and some of the prisoners accepted. -
2nd Prisoner Breakdown
The only prisoner who did not want to speak to the priest was Prisoner #819, who was feeling sick, had refused to eat, and wanted to see a doctor rather than a priest. He broke down and began to cry hysterically, therefore Zimbardo agreed to take him to a doctor. One of the guards lined up the other prisoners and had them chant aloud: "Prisoner #819 is a bad prisoner. Because of what Prisoner #819 did, my cell is a mess". -
Parole Board
All prisoners who thought they had grounds for being paroled were chained together and individually brought before the Parole Board. When asked whether they would forfeit the money they had earned up to that time if we were to parole them, most said yes. -
Parole Denial Coping Styles
Some prisoners rebelled or fought with the guards. Four prisoners reacted by breaking down emotionally as a way to escape the situation. One prisoner developed a psychosomatic rash over his entire body when he learned that his parole request had been turned down. Others tried to cope by being good prisoners, doing everything the guards wanted them to do. -
Final Act of Rebellion
Prisoner #416 coped by going on a hunger strike to force his release. After several unsuccessful attempts to get #416 to eat, the guards threw him into solitary confinement for 3 hours, even though their own rules stated that 1hour was the limit. The head guard then gave prisoners a choice. They could have #416 come out of solitary if they were willing to give up their blanket, or they could leave #416 in solitary all night.Most elected to keep their blanket and let their fellow prisoner suffer. -
Types of Guards
1st Type - tough but fair guards who followed prison rules.
2nd Type - "good guys" who did little favors for the prisoners and never punished them.
3rd Type - hostile, arbitrary, and inventive in their forms of prisoner humiliation. The prisoners even nicknamed the most macho and brutal guard in the study "John Wayne." -
Bailing Prisoners Out
Some visiting parents asked to contact a lawyer in order to get their son out of prison. Zimbardo called the lawyer as requested, and he came the next day to interview the prisoners with a standard set of legal questions. -
Calling Off the Simulation
The guards were escalating their abuse of prisoners in the middle of the night when they thought no researchers were watching and the experiment was "off." to even more pornographic and degrading abuse of the prisoners. Christina Maslach, who was brought in to conduct interviews with the guards and prisoners, was the only one who ever questioned the morality of the experiment. -
End of Study
A series of encounter sessions were held, first with all the guards, then with all the prisoners (including those who had been released earlier), and finally with the guards, prisoners, and staff together. It was also made a time for moral reeducation by discussing the conflicts posed by this simulation and demonstrated behavior.
