Bystander Effect and Diffusion of Responsibility

4 12 2011

Well I’ve heard that people are doing blogs on social psychology so I thought I’d do one too 🙂

Imagine that you’re walking down a crowded street, and you see someone suddenly collapse on the edge of the pavement. You’d like to think that you’d attend to this person and see if they’re ok, call an ambulance if needs be. But the chances of this happening are slim if there’s a large number of people there too.

The bystander effect is when the likelihood of helping behaviour is reduced due to the presence of other people in the event of an emergency. This is because diffusion of responsibility occurs; people feel that they are less responsible for helping someone in need if there are more people present.

Darley and Latane (1968) conducted an experiment in which college students would overhear an epileptic seizure over an intercom, in what they thought was a discussion about personal problems. They found that the individual’s feelings of personal responsibility and speed of reporting the seizure were lowered considerably when they were in a group with one or two more students who would have also heard the seizure. (

Piliavin et al (1969) also conducted a study on helping behaviour, where a model would collapse on an underground train, either holding a cane (ill condition) or a bottle in a brown paper bag (drunk condition). Piliavin et al found that the model was more likely to be helped in the ill condition, and that the longer the victim was not helped, the more likely it was that someone would leave the area in which the emergency was happening. However, they did not find the diffusion of responsibility effect as Darley and Latane did. They had another model sat on the train ready to help the victim after a certain amount of time ready to help the victim if no one else did, but they rarely had to do this.(

As we can see the two studies were around the same time, but both had very different results. Maybe this was due to the situation, or even the number of people. Maybe the diffusion of responsibility effect only occurs if there’s a certain amount of people. There would’ve been a very large number of people on the subway train, and maybe if there’s a large number of people, diffusion of responsibility does not occur.




13 responses

10 12 2011
9 12 2011
Blog Comments « All About Psychology

[…]… Share this:TwitterFacebookLike this:LikeBe the first to like this post. […]

9 12 2011

I really like the topic about the bystander effect, it’s a real insight into how humans behave. Latane and Darley’s (1968) experiment is a really good one to show the diffusion of responsibility but more recently, Cramer, McMaster, Bartell and Dragna (2006) show bystanders not intervening because because they feelt of lack of competence to tackle the emergency. Furthermore, Chekroun and Brauer (2002) also discussed how perceived personal obligation to act and implications in a social situation are moderated by the presence of others.Like Latane and Darley (1968) they all show how the influence of other people around can effect if you take action. Another compelling story I read in the New York Post discussed how a man was left dying on the streets of New York and no one took action. If people were more aware of the effect or other people and a lack of competency maybe more people would help? I hope so!


Chekroun, P. & Brauer, M. (2002). The bystander effect and social control behavior: the effect of the presence of others on people’s reactions to norm violations. European Journal of Social Psychology. Vol 23 (6). pp 853-867.

Cramer, R.E. McMaster, M. R., Bartell, P. A. & Dragna, M. (1988).

Darley, J. M. & Latané, B. (1968). Bystander intervention in emergencies: Diffusion of responsibility. Journal of Personality and Social Psychology pp 377–383.

9 12 2011

I like the different blog this week as it is very refreshing not to have to read about hypotheses again! With regards to this topic you have covered it very well with two different studies to make sure it is fully understood. However, take the example of one person reacting to a situation such as you described but others not. Why has this sole person broke out of the majority not reacting and suddenly gone into bystander intervention when no one other has especially when, as you said, people react quicker when others around them do as well. Is this due to their gender, experiences or something completely different altogether? i also think that you could have linked your diffusion of responsibility with the theory that people take time to evaluate the situation to see if input is a positive thing or negative and whether people have the ability to help especially if they think others around are more competent in the matter.

9 12 2011

I like how you have used two different studies of the same phenomenon and shown that their finding that contradict each other. This could be explained by the fact that diffusion of responsibility is wrong as if it was correct we should find that people will behave in the same way in the same situation which these studies show their not. For example Prevous argued that diffussion of responsibility was often confused with pluristic ignorance. Prevous study showed that more people would help when they saw someone else help than when they were on their own. Prevous argued that this was because people who didn’t help didn’t know what to do and were more likely to help if the helping behaviour was modelled and therefore not helping is due to lack of moedelling rather than responsibility.

However I don’t believe it to be the case between the 2 studies you chose as I believe that there are subtle differences between them. In Darley and Latane (1968) experiment the particpants were along and able to escape by leaving the room whereas in Piliavin et al (1969) study participant were not along and were not able to escape. These difference could explain why there was a difference in display of diffusion of responsibility.

9 12 2011

I found a lot to do with the bystander effect is to do with how people perceive the situation – if there are a lot of people around, they are less likely to help (as Darley and Latane had said) but what also plays a huge role in their likelihood to help is whether they feel competent enough to help. If the bystander doesn’t feel they possess the skills needed to be able to help, they are less likely to do so. However, if a competent person is nearby, or offers help first, they are more likely to do so (Cramer, McMaster, Bartell & Dragna, 2006).

There is also the added factor of how offering assistance is going to make them look. Audience-inhibition will discourage assistance if they feel they may be made to look stupid by offering help.

All in all, there are a number of contributing factors that must be taken into account when looking at why people won’t offer assistance, and it’s not just a clear cut as people following a crowd and refusing to help.

9 12 2011

I enjoyed reading this blog – mainly because it wasn’t statistics.

I’ve really enjoyed this terms module of social psychology and I find the bystander effect very interesting. I was shocked to find that people are less likely to help when there are more than two people present. And again I tend to wonder what I would do if this situation occurs. I would like to think that I would help, but I tend to get paniced in stressful situations and would probably feel I would make the situation worse if I did help. It’s one of those things that no one wants to admit, but research keeps showing us. People are bastards!

9 12 2011
last of the homework « whataloadofblog

[…]… Share this:TwitterFacebookLike this:LikeBe the first to like this post. […]

9 12 2011

I would argue that bystander effects are more due to the social perception of the groups then due to effect of how many people have around you (although this cannot be ignored to be at some effect– as in lectures I never speak when the lecture ask questions, but in small groups where i know people it easy to speak up but this can also be argued that this is because we perceive that it’s the wrong thing to do in lectures but ok in small groups.)
One study looked at the effects of fear of crime and type of community on bystander intervention (the two towns contrasted in crime rates). It shows that fear of crime and type of community have robust and consistent effects on bystander intervention, controlling for demographic characteristics including sex, age, and education. (
Another study investigated the James Bulger murder trial and the whiteness accounts ( It underlined how some the witnesses assumed when they saw the 3 boys must be brothers and how 2 had no intention of murder because it was deemed the more probable assumption by society.
However, i woule agree that bystander effect can be affected by may facters.I personaly find that people act diffrently around large group of strangers because of anixety. Alot of people dont have this problem but may, not speek up in lectures because they find it silly, deemed silly by the group or was not listening.

9 12 2011

I also tend to think what i would do in this situation. I do think that Piliavin’s results are interesting as i think the nature of the incident has an affect on diffusion of responsibility. For example if someone was evidentially ill then i would like to think i would help in anyway i can and use my skills of first aid in order to assist which Korte, 1971 says helps increase peoples confidence. However i do think that if the incident involves violence I would show diffusion of responsibility in order to protect myself, as I know i would probably get hurt and be of little assistance. However i would definatly contact someone who could be of assistance and not just walk on and carry on with my day.

According to other research it is interesting to look into other factors which are likely to influence us to help. According to Shotland & Heinold, 1985, if you are in a familiar environment you are more likely to help and also if you know the victim this will also make you feel more responsibility to help (Christy and Voigt, 1994). In addition your mood influences you to help and happy people are more likely to help, also people from small towns (Latane and Darley. 1970).

In conclusion many off these factors do apply to me which shows I am likely to help, however i do believe the saying do to others as you would have done to you and would hope that the reciprocity principle that I had social responsibility to behave in that manner and to treat people how I would want to be treated in same situation would be a major influence.

8 12 2011

It is really interesting how diffusion of responsibility makes people less likely to help. The natural reaction is, the more people are around when an incident occurs, the more quickly help will be provided. But the bystander effect contradicts this. However there are exceptions to this effect. For example this study by Cramer, Mcmaster, Bartell and Dragna (2006) found that people who were confident that they had the skills to help the person in need (such as nurses) did not experience the bystander effect.

6 12 2011
6 12 2011

An interesting topic, and each time I have read or listened to this theory I always go off into my own little world and think “what would I do?”, and I always think that I would help.
Maybe it depends on the situation because apparently, and I didn’t know this until just now when I googled it, but Britain is known as the ‘bystander community’, but according to this news article research has found that us Brits are actually more likely to intervene than walk away ( It is apparently in our makeup (not the cosmetic kind) to behave in an altruistic manner, but unfortunately some people just walk away. There are many examples of this, and I’ve just read about a 20 year old gap year student who got stamped to death, because she was dressed as a Goth, and although people were passing by, it is reported that no one did anything to intervene ( I can understand that people are scared of being hurt themselves, but how can they walk away from something so horrific, with the knowledge that that person is going to die if nothing is done?
I think if I was in that situation I would do something, I’m often nicknamed a small snappy dog, the name escapes me now, I think it’s a terrier, or maybe a jack Russell, anyway the reason for that is well I’m small and snappy! But if I see someone upset, I always want to help because that’s the person I am. Sorry I’ve gone off the point slightly, what I was trying to say that I don’t think I could just walk by. I had a dream once that my mums handbag got stolen while we were in a cafe in Sainsbury’s, and I ran after the man who had stolen it and ended up getting stabbed, but that doesn’t put me off I’m sure I would intervene. But I guess you never really know until it happens.
One last thing before I end this comment, I was watching crime stoppers about a month ago, and a man who was cycling home witnessed a girl being sexually assaulted and he intervened and stopped the girl from being hurt any more than she had been already. I thought that was amazing, and I thought to myself as I often do, I bet there wouldn’t be many people that would have done that.
But back to my comment of us Brits being more likely to intervene than walk away, Dr Mark Levine has found after watching CCTV footage that there are a great number of people who don’t walk away, and I think this is pretty commendable.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: