No one thought the experiment would have any big problems - the participants were just playing a short game of prison. Yet in less than a week the prisoners were becoming psychologically disturbed, and the guards disturbingly sadistic. There were riots, hunger strikes, and abusive treatment - all in the mock-up jail cells created in the halls of the Stanford psychology department. The study had to be canceled early, leaving one critical question - how could a fake prison situation become real so quickly?
The problem couldn't have been the characteristics of the participants. The original twenty-four volunteers were picked for their stability of mind, out of a group of seventy. Also, the pick between the prisoners and prison guards was made at random via coin tosses. Thus, there was no bias when it came to the players.
Zimbardo did attempt to make the prison more real with some degrading tactics to simulate a real prison. Each prisoner was given a number that was their identification for duration of the experiment. As for clothing, a prisoner only got one ill-fitted Muslin smock, an uncomfortable pair of rubber thong sandals, and a nylon pantyhose cap (which was put over the head, as though they had a shaved their hair off). If that wasn't bad enough, each had a chain on their foot, its constant clinking specifically to remind them that they were not free.
On the chosen start date, the prisoners were arrested for armed robbery and taken from their homes by the actual Palo Alto police, who cooperated with the project. Their arrival at the pseudo-jail was as nasty as in any prison - they were stripped naked and deloused, then given their uniforms and numbers. And so the simulation began.
The first day of the experiment was relatively peaceful. Then, on the second day, the prisoners got feisty and attempted a rebellion. They took off their stocking caps and numbers, as well as barricading their cells with their beds. The guards took this threat seriously, calling in reinforcements to solve the problem. In the end, they used fire extinguishers to blast the prisoners away from the doors, then rushed in, stripped them naked, and sent the ringleaders into solitary confinement.
To further break the rebellion they used some mind games on the remaining prisoners; some were put in "good" cells where they were treated nicely, where the rest were put into “bad” cells where they were mistreated. After half a day, some of the prisoners were switched, thoroughly confusing the prisoners. Had someone ratted on another? Were there informers in their midst? Further rebellions were crushed.
This environment got to be too much for some of the participants. Within two days, one prisoner began to have an emotional breakdown. However, at this point the guards started taking their roles very seriously - they thought he was trying to get out of his time by acting crazy. The participant soon became convinced that there was no escape from the study and went into a rage, an action that was finally enough to prompt his release from the study. He was not the only one who was released from the study early, and many others who stayed suffered from uncontrollable crying and disorganized thought.
Tauntingly, there were offers made to the prisoners to go on early parole. When asked if they'd sacrifice their payment in the study to get out early, most said yes. However, all paroles were rejected. Even though they had no incentive to continue in the study, they went with it anyways - as though they were really stuck in prison. Not that the guards would have let them free– as time went on the guards became more involved with their end of the study as well.
There were many more abuses, as each day the guards became more controlling and the prisoners more disturbed. Despite all of this, visitors to the study did not seem to see any serious problems with the experiment. One day the friends and family of the prisoners were invited to visit them. Though a few made small protests to the participants' treatment, no one insisted upon the end of the study. Later, a chaplain came to visit with each of the prisoners, and he also voiced no objections.
However, in the end the experiment was canceled when a woman named Christina Maslach came to visit the Stanford prison. After seeing the crazy state that the prison had fallen into, she was outraged at the terrible conditions of the whole situation.
The researchers' overall conclusion in the study was that people fit their roles to institutions surprisingly well, despite their individual differences. That is, their situation dictated how they acted, rather than their own dispositions. However, this study has been highly criticized due to its unethical nature as well as its generally unscientific nature (can you imagine tracking all the variables?)
Still, it's undeniable that there's something more to the human mind than we think if such normal, stable people can become so degraded or monstrous in only a week's time. The prisoners, normal before the study, were quickly trapped in their own real prison. The guards were vigilant and kept the prisoners from escaping, despite their disturbed states. And thus a controlled scientific simulation quickly deteriorated into reality.