00:00 – Introduction

01:07 – Methodology of the experiment

03:41 – Conclusions drawn from the experiment

04:41 – Why was it controversial?

09:40 – What if the experiment was to be done again?

12:54 – Their experiment

17:50 – Take-aways from the episode

19:19 – Ending and outro


You can listen to The Method Section by using the player above, searching for “The Conduct Science Podcast” on any place you listen to your podcasts, using any of the links below or you can download it HERE!

This week on The Method Section, Tom takes a look at The Stanford Prison Experiment. Possibly the most famous psychological experiment ever conducted, but maybe for the wrong reasons! The results nonetheless are used all over the world in court rooms to justify people’s actions. But what if the conclusions are invalid? And if it were to be done again, how would it be done? Music by: Joakim Karud – https://soundcloud.com/joakimkarud.

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The Method Section: The Stanford Prison Experiment – Transcript

Tom:                      Hello Ladies and gentlemen and welcome. I am your host Tom Jenks and today I’ll be talking about the Stanford prison experiment. It’s background, the methodologies and conclusions drawn from it, why it was so controversial and what if it were to be done? Again, stay tuned to The Method Section

Tom:                      Yes. Today in The Method Section, a short form series aimed at scientists. I will be taking a look at the Stanford prison experiment, one of the most infamous psychological studies ever conducted, unfortunately mainly for how unethical it was. This was an experiment conducted in 1971 by Dr Philip Zimbardo and the conclusions drawn from this were how anyone in the right circumstance would become evil or cruel. However, this wasn’t the original purpose of the study. The original purpose of the study was to look at the psychology of prison life, so let’s jump straight into the methodologies.

Tom:                      So 75 people applied to an advertisement asking for men to help in a prison experiment. 24 of these were selected for this two week experiment based on their mental capabilities and stability. They were all in kind of the the mid range for this. 12 of them were randomly selected to be the guards. The other 12 were randomly selected to be the prisoners and on August 14th, 1971 in California, 12 of the prisoners were arrested in their own homes and taken to a fake prison located in the basement of the Stanford University. The prisoners were blindfolded on their way to the prison. When they got there, they were stripped, made to wear prisoner frocks. They had shackles on their feet and they were given numbers. They were no longer referred to by their name. They were referred to by their prison numbers. Now, what happened was very quickly the guards stepped into their role. Within a matter of days, they were cutting the food supply. They were cutting bathroom use. They wouldn’t let prisoners wear underwear and they started to use force excessively so. On day one everything was kind of normal. Then suddenly on day two, what they termed as the rebellion happened, this is where at 10:00 AM the prisoners were mocking the guards and refusing to leave their cells ready for prison call. The guards then not obviously liking this and feeling provoked from this. They used fire extinguishes to get the prisoners back from the doors and they forced their way into the rooms, stripped the prisoners naked and took the beds out of the room. This is day two on day three then the prisoners had a visitation day from family members and for fear that they would be taken away because of the, they’d gone too far. The guards cleaned up the prisoners, gave them meals, but also on this day, prisoner #8612 had a break down and suffered some uncontrollable crying and rage and over the next few days this just increased. This just got worse and worse. By the sixth day, the experiment had to be canceled. Things were just so far out of hand by this point that the experiment is doctor Philip Zimbardo and the rest of his team had to cancel it because the guards were just going too far at this point.

Tom:                      So the conclusions that they drew from this were that evil is inside everyone and it just takes the right circumstances to bring it out. The circumstances being anonymity because the prison guards had uniforms on, they had big sunglasses mirrored sunglasses on, so they had that anonymity and they had power over these depersonalized people who weren’t even allowed to use their names anymore. This experiment is also used to illustrate the cognitive dissonance theory quite a lot as well, and since it made international and national news Zimbardo’s fame rose very quickly. The conclusions were accepted mainly and his findings are used all over the world in court and medical cases to explain why people did certain things. Maybe in a court case and they get more lenient sentencings and things like this.

Tom:                      So why was it so controversial? The first reason is pretty obvious. It was highly unethical towards the participants, especially the prisoners. Very traumatic things happen to them and if you watch the videos, not all of it is easy to watch. They are screaming that they don’t want to be part of the experiment anymore. Secondly, the conclusions drawn from this could be invalid. And now this is, this is a very important point because if the findings are being used across the world in court cases and medical cases, this is something that needs to be addressed. So the reasons why they think the conclusions could be invalid, and these kind of theories might be wrong, is that there are a lot of experimental biases or there are a lot of alleged experimental biases. It’s, it’s very complicated and some parties say some stuff happened and other parties say it didn’t. So it’s kind of a detective story trying to figure out what really happened.

Tom:                      However, there are some things that we can draw from that and that we can see there were some biases maybe so the guards were given sunglasses and batons upon arriving this gives them anonymity and the fact that they were given a baton, doesn’t that make them consider that physical force is maybe acceptable or what maybe the experimenters, are looking for? There are lots of things that aren’t done in a normal prison that were done here. So the prisoners were blindfolded upon entering and on their way in. They were made to wear women’s clothing. Bearing in mind, all of the participants were men. They weren’t allowed to wear underwear. They weren’t allowed to look out of windows. They weren’t allowed to use their real names. Now, this isn’t an accurate representation of a real prison. However, I couldn’t find anywhere that this, some of this at least wasn’t completely down to the guards, the acting guards, so obviously the prisoners being blindfolded and not using their real names was part of the experiment definitely. But the other things, I don’t know if that was just controlled purely by the guards and no outside input. Looking back at this Zimbardo has made some quotes over the years, but he still stands by the experiment and what he did. However, he has had this to say on the controversiality of it all. He has said that he wasn’t merely an observer, but an active participant in some cases that influenced the direction of the experiment. With this, he is referring to given the guards sunglasses and batons and other things like this. In 2008 Zimbardo did actually give a quote. And it is this, it wasn’t until much later that I realized how far into my prison role I was at that point that I was thinking like a prison superintendent rather than a research psychologist. So his cover within this experiment was that he was the superintendent and that allowed him to kind of come in and observe. However he’s saying maybe even he got too trapped into the role of that superintendent. There are some claims that the guards were told to be tough. And this is something that I’ll come onto later, which is obviously a completely another bias and adds on to my next point. One of the reasons why it’s so controversial and one of the reasons why the conclusion shouldn’t be taken in the way that they are, is that there is the problem of demand characteristics. So this is where a subject of an experiment behaves differently to what they normally would because they wanted to give the experimenter what they were after. They want to help the experiment. And this is definitely what interviewees who were actually the prison guards have said. So apparently the guards are told to be oppressive or tough. So the question then becomes, if you tell people to be cruel and you tell them it’s for science, it’s for the greater good. Do they lose the moral boundary that they had? Do they that they escaped the morality that they should have and the consequences of their actions because they are in an environment where it is okay? Zimbardo however, does claim that this wasn’t the case. He says demand characteristics did not play a factor.

Tom:                      So then that brings us on to the interesting, not even thought experiment, I guess, of if these conclusions are to be invalid. What if the experiment was to be done again? So Vsauce actually did this. Vsauce is a massive science-based channel on Youtube and I would recommend to go check it out. And this is one of their free episodes as they’ve stepped into the monetization side of youtube. However, this is a recent and free one, so go check it out. So Michael Stevens from vsauce did this in with Jared Bartel’s who’s an American psychologist and he’s written a lot about the Stanford prison experiment. And he says if you were to do it again, you would need to get rid of the demand characteristics. You would need to have a good cover story. So one of the problems they thought with the original Stanford prison experiment is the advertisement asked for men who would want to take part in a prison experiment. Does that not narrow down the type of people who want to participate? The type of people who are going to engage in something like that might already have a aggressive predisposition. Zimbardo’s counterclaim to this was, you know, they did lots of personality tests over the 75 people that applied and the 24 who were most, not average, but down the middle where the ones that were put into the experiment, uh, everyone who had prison experience or used drugs or was unstable in any way was disregarded from the experiment. And they use the most stable people they could. The next thing you would have to keep in is the depersonalization of the subjects. For example, giving them the numbers instead of the names. Then you would have to keep the anonymity. The subjects need to believe that no matter what their actions, the cruelty or whatever happens won’t be traced back to them. Next, there needs to be power differences, so they need the ability to be evil. They need to know they are in a position where if it’s true, that evil comes out in everyone. When there’s anonymity, depersonalization, and power, they need to think that they are in a position of power for this evil to come out. And lastly, they need provocation. They need a reason to exercise this power difference that they have. In the Stanford prison experiment, it was the rebellion or the so named rebellion from the prisoners.

Tom:                      Now, what you need to just bear in mind is the Stanford prison experiment wasn’t originally there to test this. The Stanford prison experiment was just doing psychology on prison life. So this experiment then if you were to try and test the same conclusions that came out of the Stanford prison experiment, these are the things you would need to keep the same to test those conclusions.

Tom:                      So the experiment that they went through, then they picked eight people from the number who applied, who all tested high on morality characteristics. So this is conscientiousness and honesty and things like this, compared to the Stanford prison experiment where they were the type of people who applied for a prison experiment and might have a predisposition to be a bit more angry even though they were down in the middle on the charts that cover and then so they had to have a good cover story. They said what they were gonna do is invite four people into a dark room and see how effectively you can solve puzzles. They kept the depersonalization, they gave participants numbers. You are participant number one, you are participant number two and so on. And the anonymity was maintained by the subjects not meeting before and being in a completely dark room. The power then came from the fact that they were told a second group. So the group of four they were told a second group was in the other room doing the same thing and under next to their chair they had a button that they could press that would play a noise into the other room and they could pick how loud that noise was. On a scale of one to 12 anything above seven was harmful to the ears of the people listening to it. It could cause serious harm to their hearing. So then if they were evil, you would expect them to press the buzzer and have it higher than a seven.

Tom:                      They did this with two groups, so they brought the first group in and said, okay, complete the puzzle and they played a buzzer into their room to trigger a response. This is the provocation section. So they played a noise into their room. The experiment is there, there was no second group, so there was no chance of a second group being harmed by someone turning up their buzzer loudly. Group One heard the distraction noise 23 times and only pressed it six times between the four of them. None of them pressed it higher than five. The second stage of the experiment was to come in and tell the subjects that they didn’t have to do the puzzle anymore. All they had to do was press the button to annoy the other group. This was to give them a demand characteristic to see if when told to do so, they would put other people in harms way. However, over the next 10 minutes, they only pressed it three times and no one pressed it higher than level five so you would presume none of these people were evil.

Tom:                      In group two. So in the first stage when they were just trying to complete the puzzle and they had the distraction noise coming in, they heard it 44 times and they pressed it 38 but 37 of them were from one person and it seemed like that person was only doing it in retaliation. When they were hearing a noise, they would do the noise back. They then stopped playing the noise and the person stopped pressing the button in Stage two and they were told it’s their only job to distract the other team and they didn’t have to do the puzzle anymore. O-o-okay, they pressed it quite a lot. They, I think it was in the 60s that they pressed that button. However, it was never at an unsafe level, so okay. Whilst they might have been causing an annoyance to the other team, fictional team, there was no one there. They were never cruel. They never put it above seven. They never intentionally harmed someone.

Tom:                      Vsauce then took this experiment to Zimbardo saying that they showed evil doesn’t come out of just having anonymity power over a depersonalized person. Zimbardo then said to this that, well they had a personality bias. They pick people that were very honest and high on morality characteristics and they, this is an example where the personality really control the situation and they were there, kind of had a little discussion about where is the line, where the situation controls the person and personality controls the situation and that is it. The big question. That is the question. In this field of psychology that is still unanswered, so it would appear that there are both situations. It would appear that there are both scenarios. One where the situation controls the person and one where the person controls the situation. And maybe it depends on your personality.

Tom:                      So bringing this to a close, we originally drew conclusions about people being evil from an experiment, not designed to test that. Whilst it could and they drew fairly what seemed like logical conclusions at the time. It wasn’t exactly designed for that. And obviously they couldn’t repeated due to ethical reasons.There were then lots of reports over the years coming out about biased interactions, demand characteristics, the guards being told to be tough and things like this. So does that mean in this day and age where the results of that experiment are being used to influence decisions in court and in medical scenarios? Do we need to rethink about how we interpret that data? The answer is obviously a tricky one and I think something that maybe we don’t have, it does seem like people with predispositions will act a certain way. And in some scenarios people act a completely different way and we as Zimbardo said himself, he doesn’t know where the line is between the scenario controlling the person or the person controlling the scenario. It is a debated forefront of psychology and one that’s very interesting and I think we will see advances or hope we will see advances in the near future to do with it.

Tom:                      However, this is meant to be a short form podcast no longer than 20 minutes and I believe I am coming up to that or over it already so I’m going to end it here and leave you with that question. If you want to get back to me with your response, please hit us up on Facebook or Twitter by searching at @conductscience. Maybe if you have a question you can use the #AskConductScience and if you want to check out all the latest goings on from us, you can go to conductscience.com next week on The Method Section. I will be talking about being wrong, why it’s a good thing and why it’s not something to be afraid of in science, but that’s it from me. So I’ll see you guys. A-next time