The Stanford Prison Experiment

By: Annika Getz

In August of 1971, the Stanford University psychology department led an experiment which was meant to test the effect of prison life on the inmates. Stanford psychology professor Philip Zimbardo constructed the “Stanford County Jail” in the psychology building basement. The cells were created by taking doors off of lab rooms, and replacing them with doors made specially with cell numbers, and steel bars. Inside the cells, there was room for three cots, and little else. There was a corridor which they called “The Yard”; this was the only place where the prisoners could walk, exercise, or eat. If a prisoner needed to use the restroom, he was blindfolded and taken down the hall, this way they didn’t know the way out of the prison. There was also a small closet opposite of the cells which was used as solitary confinement.

Cameras and intercom (which made it possible to bug the cells, as well as make announcements to the prisoners), allowed the experiment leaders to monitor the guards and prisoners at all times. There were no windows or clocks in the prison.

The guards and prisoners were college students, who had responded to an ad posted in the local newspaper. They were then given personality tests, and diagnostic interviews, so as to eliminate candidates with mental health issues, medical disabilities, or histories of crime or drug abuse. Over 70 applicants answered the ad, and 24 were left after the interviews. These 24 were randomly assigned to be either prisoners or guards, and promised 15 dollars a day for participating in what was supposed to be a two week experiment.

On the day of the experiment, the volunteers were gathered via a mock mass arrest. Real police cars came through and picked them up at their houses, and charged them with anything from a Penal Code violation to armed robbery. They were searched and handcuffed, in front of their families and neighbors, who of course, didn’t know of the experiment.

Once they arrived at the prison, they were met by the “warden”, who was an undergraduate at Stanford, David Jaffe. They were then fingerprinted and identified, and taken to a holding cell, where they were blindfolded and left to wait. Each prisoner was then stripped and searched, then deloused with spray. They were given uniforms of smocks, with their prison ID numbers (which is all they were referred to as, never names) on the front and back, and a stocking cap (to simulate real prisoners’ heads being shaved). The final item of their uniform was a chain worn on their feet at all times. It was made in such a way that when a prisoner would turn in his sleep, the chain would hit his other foot, so even in sleep he would remember he was in the prison.

The guards were not given any training, they made their own rules, and were allowed to do whatever they wanted (within reason) to enforce these rules. They were dressed in khaki uniforms, with a whistle around their necks, a club borrowed from the police, and mirrored sunglasses so their eyes couldn’t be seen. In the beginning, three guards would work eight hour shifts, while three prisoners occupied each three cells. The guards fell into their roles quickly and rashly, coming up with creatively sadistic punishments, such as forcing prisoners to do pushups while a guard or fellow prisoner stepped on his back.

On the first night, the prisoners were woken by blasting whistles at 2:30 A.M., the whistles signaled for the first of many “counts” where the guards called the prisoners numbers for roll call. These counts happened several times during a shift, very often at night, and allowed for the guards to show their control over the prisoners.

On the morning of the second day, a rebellion broke out. The prisoners took off their ID numbers and stocking caps, and barricaded the doors to their cells with their beds. They then cursed out the guards, who quickly became agitated. When the morning shift arrived, they were upset with the night shift, blaming them for the prisoner’s outburst. The morning shift demanded reinforcements, and the night shift guards agreed to stay on to help handle the situation, three guards on stand-by at home were also called in.

Using a fire extinguisher, the guards shot the carbon dioxide at the prisoners, forcing them away from the doors. They then broke into the cells, stripped the prisoners, took their beds, and took the rebellion leaders into solitary confinement. The guards then decided that in order to squelch any future rebellions in its tracks, they would use psychological tactics to manipulate the prisoners. They ended up creating what they called a “privilege cell”. The prisoners least involved with the rebellion were put in the cell, and given their beds and uniforms back, allowed to brush their teeth, and were given special food to eat around the others, who were temporarily not allowed to eat. However, after half a day of this, the guards took the prisoners who had participated in the rebellion into the “good cell” and the ones who hadn’t in the “bad ones”. This of course, confused the prisoners, who came to the conclusion that the leaders of the rebellion were secretly informants, which led to a breaking of alliances amongst the prisoners.

The rebellion also brought a greater sense of “us vs. them” to the guards, who now, rather than seeing the prisoners as just other college students, saw them as troublemakers, who were out to cause problems.

Less than three days into the experiment, prisoners’ #8612 psychological state worsened significantly. He was crying uncontrollably, his thinking was disorganized, he was enraged. Rather than letting him go, or doing a real evaluation of his mental state, the organizers found themselves so enthralled in their own experiment, that they thought he was faking it to be released. When they had the prison consultant interview #8612, he was chided for being weak, and told about the abuse he could have expected in San Quentin Prison.

In a later interview the “prisoner” said “I was told that I couldn’t quit, and at that point I felt that, well, it was really a prison, and at that point—I don’t know I just—there’s no way to describe how I felt, I just felt totally hopeless, more hopeless than I had ever felt before.”

During the next count, the prisoner told the others “You can’t leave. You can’t quit.” He then began screaming and cursing, in a seemingly out of control rage. Finally, the organizers deemed him as truly unstable, and released him. The prisoners were left with the line between reality and experiment blurred in such a way which left them feeling as hopeless as #8612 had.

The following day, visiting hours were held. Worried that family and friends would want their sons released upon seeing the state of the prison, the organizers decided to clean up the environment. The boys were washed, their cells were polished, and they were given a big dinner. Music even played over the intercoms.

Still early on in the experiment, the organizers heard rumor of an escape plot. Rumor was that #8612 was going to gather his friends, and break in to free the prisoners. The organizers did not respond to this rumor as psychologists. They didn’t let it play out and record the results, rather, they responded as prison wardens and superintendents. Concerned for the security of their prison, they put an informant in the cell that had been #8612’s. They even asked the Palo Alto Police Department if they could transfer the prisoners there. The request was, of course, denied. Instead, the organizers had the guards chain the prisoners together, put bags over their heads, and bring them to a storage room in the building. The rumor however, ended up being false. The plot to escape never came to be.

A Catholic priest was then invited to evaluate how realistic the simulation was. When interviewing the boys, he told them that if he wanted them to, he’d contact their parents to get a lawyer. Some of the boys accepted this offer.

Prisoner #819 was the only prisoner who wouldn’t speak with the priest, he was sick, and refused to eat, wishing to see a doctor. When he was eventually persuaded to come out of his cell, he broke down, crying hysterically. His cap and chain were taken off, and he was then sent to wait in a different room for a short time, until Dr. Zimbardo could get him food, and take him to a doctor. While Zimbardo was doing this, a guard lined up the prisoners, and had them chant “Prisoner #819 is a bad prisoner. Because of what Prisoner #819 did, my cell is a mess, Mr. Correctional Officer.” They chanted in unison again and again, as though they were one unified voice, whereas on the first day, their voices had been messy, and disorganized.

While they were chanting, Dr. Zimbardo realized that #819 could hear them from where he was waiting. He raced back to find the boy sobbing uncontrollably, listening to his fellow prisoners, his peers chant that he was bad. When Zimbardo suggested that they leave, #819 refused, saying he had to prove he was a good prisoner. Zimbardo then told him, “you are not #819, you are [his name], and my name is Dr. Zimbardo. I am a psychologist, not a prison superintendent, and this is not a real prison. This is an experiment, and those are students, not prisoners, just like you.” Only then did the boy’s crying stop, and he agreed to leave.

The final rebellion seen in the experiment, was done by Prisoner #416, a standby prisoner who’d been admitted to replace the few who had been released. This boy arrived at what was basically a horror show, and was told by the others that you couldn’t quit, it was a real prison. In response, he went on a hunger strike, so the organizers would have to release him. The guards put him in solitary confinement after unsuccessfully trying to get him to eat, he stayed there for up to three hours, despite their own rules stating that the limit was an hour. #416 still refused to eat.

The guards proceeded to tell the other prisoners, that if they gave up their blanket, and slept on their bare cots, then #416 would be let out of confinement. Most prisoners elected to keep their sheets, seeing #416 as a troublemaker. #416 would have been left in confinement all night, had the organizers not stepped in to lead him back to his cell. Later, #416, who’s real name was Clayton, remarked about feeling as though he was losing his identity.

On just the fifth night, parents began requesting for lawyers to be contacted after talking to the priest who had interviewed their sons. It was at this point that the organizers knew they had to end the experiment, their simulation had been so powerful, that the prisoners were having pathological responses, and the guards (who the personality interviews deemed perfectly normal boys), either became sadistic, or felt hopeless to intervene. They were further prompted to end the experiment when watching the videotapes of the night shift. The guards, thinking that the researchers weren’t watching, escalated their abuse of the prisoners, presumably due to boredom. The final reason they ended the study was the objections of Christina Maslach, a Stanford Ph. D brought in to conduct interviews with the boys. Because of all this, the study ended only six days after beginning.

This experiment remains to be one of the most well known psychology experiments ever conducted, coming to the conclusion that people do, or become things, they wouldn’t expect from themselves when placed in the correct environment.

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