Evil acts, we like to think, are the preserve of psychopaths. Yet 30 to 40 years ago, a series of classic psychology experiments showed that the behaviour of ordinary people can be transformed in groups and that the most decent of individuals can be led to behave in the most indecent ways. These studies raise critical questions about the processes through which groups can transform us, and whether such transformations are always for the worse. Yet for decades it has been impossible to conduct studies with the same power as the classic studies and to interrogate their conclusions. The BBC Prison Study has broken this impasse and provides a surprising new set of answers with important social, clinical and organisational ramifications.
Evil acts, we like to think, are the preserve of psychopaths. Yet 30
to 40 years ago, a series of classic psychology experiments showed that
the behaviour of ordinary people can be transformed in groups and that
the most decent of individuals can be led to behave in the most
indecent ways. These studies raise critical questions about the
processes through which groups can transform us, and whether such
transformations are always for the worse. Yet for decades it has been
impossible to conduct studies with the same power as the classic
studies and to interrogate their conclusions. The BBC Prison Study has
broken this impasse and provides a surprising new set of answers with
important social, clinical and organisational ramifications.
Are groups ‘naturally’ bad for us?
Of all the demonstrations that groups can change us, perhaps the most
extreme was conducted by Philip Zimbardo and colleagues at the
University of Stanford in 1971 (Haney, Banks & Zimbardo, 1973). In
this, ordinary young men were divided randomly into prisoners and
guards and placed in a prison-like setting. Very quickly, some of the
guards began to act brutally. They set out to humiliate the prisoners
and to deprive them of their rights. Within days, some prisoners began
to develop psychological disorders. So severe were the consequences
that a study scheduled to last a fortnight had to be terminated after
only six days.
The Stanford Prison Experiment (SPE) provided a grimly compelling
portrait of the power of circumstances to shape behaviour. This is the
main reason why its findings are well-known even beyond the boundaries
of academia. But the SPE didn’t just show the depths that people can
descend to in groups, it also sought to explain exactly what caused
this descent. To those who ran the study, it illustrated a general
tendency for people in groups to lose their capacity for judgement and
agency and hence to become helpless to resist antisocial impulses.
Groups are inevitably bad for you. Groups with power inevitably abuse
it. Or, in the researchers’ own words, the aggression of the guards
‘was emitted simply as a “natural” consequence of being in the uniform
a “guard” and asserting the power inherent in that role’ (Haney et al., 1973, p.12).
A powerful phenomenon… but a questionable explanation
Although few doubt what happened at Stanford, there are in fact good reasons
to doubt Zimbardo’s explanation of the events. If it is ‘natural’ to
abuse power in groups, why did only some guards behave this way? And if
only some guards were brutal, was this ‘natural’ or was it a product of
Zimbardo’s leadership? After all, in his briefing, Zimbardo instructed
his guards by telling them: ‘You can create in the prisoners…a notion
of arbitrariness, that their life is totally controlled by us, by the
system, you, me – and they’ll have no privacy… We’re going to take away
their individuality in various ways. In general what all this leads to
is a sense of powerlessness.’
There are also moral reasons to doubt the ‘role’ explanation. It suggests that all
of us would mindlessly abuse others if we were given roles that
appeared to demand this. This denies the capacity for human agency and
choice (Reicher & Haslam, in press). And it suggests that –
whatever position they occupy in the social hierarchy – bullies and
tyrants are passive victims of psychology who cannot be held
accountable for their actions. In this way, psychological analysis
easily ends up excusing the inexcusable (Haslam & Reicher, 2006).
Beyond Stanford – The BBC Prison Study
We have been stuck with this questionable explanation for a whole
generation, because the behaviour that lent the SPE impact made it
unethical to repeat. How can we advance understanding of the psychology
of tyranny without ourselves being tyrannical?
This was the dilemma that confronted us when we set to work on a new
‘prison study’ in 2001. This ended up being one of the largest
experiments in social psychology since the 1970s. The study we
conducted – referred to as the BBC Prison Study – was a collaboration
between ourselves and the broadcaster. It was filmed by the BBC and
televised in four hour-long documentaries in May 2002.
Yet even before the study was run, and certainly after the
documentaries were aired, the BBC Prison Study attracted considerable
controversy – much of which was aired in The Psychologist. Was it just
a piece of reality television with no serious implications? Can
collaborations between the media and academia ever be of scientific
value? Can broadcasting psychological research be ethical?
These were valid fears. That is why we negotiated a unique contract
with the BBC whereby we, the scientists, would design, run and analyse
the research (as we would in any other study) while the broadcaster
recorded and transmitted key elements of the research. The television
documentaries themselves were not the full scientific story, but rather
were designed to provide ‘a window on the science’: something that
might get people interested and motivate them to find out more for
However, the process of producing television documentaries moves much
more quickly than that of performing scientific analysis and securing
scientific publication. So, for a long time these documentaries were
the primary form of information about the study that was in the public
domain. It is only now that, in the words of The Guardian’s John
Sutherland (2005), The Experiment has ‘crossed back into academia’. So
it is only now that is it possible to assess the scientific merits of
the exercise. Did it provide any worthwhile insights into the
psychology of group behaviour and misbehaviour? And did it do so with a
rigour that meets the standards required for scientific publication?
a particularly pertinent question in light of the fact that the
findings of the SPE were never published in a peer-reviewed psychology
The answer to the latter question is clear. The study’s key findings
were first summarised in Scientific American Mind (Haslam &
Reicher, 2005) and in a more detailed exploration of tyranny in the
British Journal of Social Psychology (Reicher & Haslam, 2006).
Additional publications also explore a broad range of social, clinical
and organisational issues including agency (Reicher & Haslam, in
press), stress (Haslam & Reicher, in press-b), leadership (Reicher
et al., 2005) and organisational behaviour (Haslam & Reicher, in
press-a). Indeed, to our knowledge, the study has generated more
peer-reviewed publications than any previous social psychological field
As to the former question – did the study provide any worthwhile
insights? – the answer obviously depends upon the judgement of those
who read our work. However, for us, one of the contributions of the
study is already implied in the range of outputs it has led to.
Characteristically, in our everyday studies, psychologists tend to
focus on a narrow set of phenomena and collect a limited range of data.
We thereby perpetuate arbitrary disciplinary divisions between domains
that one might expect to be interrelated. In nearly 10 days of constant
data collection – which incorporated observational, psychometric and
physiological measures – we were able to examine how relations within
and between groups developed and impacted upon each other. We also had
space to investigate clinical and organisational as well as social
psychological issues. We were thereby able to see how phenomena that
are of core concern to us as social psychologists (notably, the
presence or absence of a shared sense of social identity) are related
to the mental well-being of individuals and the health of social
systems. Although it has been hypothesised that there is a link between
these elements (e.g. Ellemers et al., 1999; Haslam, 2001), no single
study had demonstrated that the phenomena are interrelated, elucidated
how they are interrelated, or explored how their relationship unfolds
Procedure, ethics and rationale
In what ways, then, did the design of our study differ from the SPE?
The study used the same basic set-up as Zimbardo’s study and divided
people randomly into prisoners and guards. However, unlike Zimbardo, we
did not act as prison superintendents who instructed the guards how to
act. We simply set up a situation in which the guards had authority,
had the tools of power and had better conditions (food, living
quarters, etc.) than the prisoners. Our intention was to create a
situation that was harsh and testing, but not harmful. In order to make
sure we got the balance right, our study was also overseen by clinical
psychologists and an independent ethics committee chaired by an MP.
On the basis of social identity theory (Tajfel & Turner, 1979), we also planned
a series of interventions designed to impact on the level of shared
social identity among the prisoners and thereby to increase their
willingness to resist the guards’ regime and any tyranny associated
with it. Using systematic observation (aided by unobtrusive filming)
and daily administration of psychometric and physiological measures, we
then observed how both groups reacted.
Although we set the study in a prison-like environment, our primary
goal was not to mimic a real prison. That would have been impossible as
well as unethical. What was real, however, was the fact that one group
(the guards) had more power and resources than the other (the
prisoners) – a feature that is also characteristic of a wide range of
institutional environments such as offices, schools, factories, and so
on. Our interest, like Zimbardo’s, was then to use our findings – and,
more specifically, the theoretical analysis they support (Turner, 1981)
– to comment more generally upon how people respond to social
inequality. When do the powerful embrace inequality and abuse their
power? When do the powerless succumb to oppression or reject and resist
it? And what is the role of the group in these processes?
The Guard–Prisoner Regime: Solidarity and well-being
What we found can be divided into two phases. At the start of the
study, both groups felt distinctly uncomfortable with the exercise of
power and with inequalities they encountered. This is understandable in
the case of the prisoners. It meant that, as time went by, they
increasingly banded together as a group in order to challenge the
authority of the guards. It is, perhaps, somewhat more surprising in
the case of the guards, who were never willing to embrace their
position and exert their authority. So, rather than passive prisoners
and brutal guards, we observed rebellious prisoners and ambivalent
guards – some of whom were keener to befriend the prisoners than to
punish them. Our participants showed no ‘natural’ tendencies to slip
helplessly into role.
The fact that the prisoners came to share a group identity while the
guards did not is important in itself. But some of the most interesting
findings in the study have to do with the consequences of this
contrast. These are summarised in Table 1 [PLEASE DOWNLOAD THE PDF
VERSION FOR THE TABLE]. Amongst the prisoners, social identification
led to agreement and mutual support. This in turn led to effective
coordination, agreed leadership and organisational effectiveness. They
worked together and were thereby empowered to turn their goals, beliefs
and values into social realities. This collective self-realisation both
increased the initial level of group identification and was in turn
good for the psychological well-being of the prisoners. Their levels of
depression and burnout decreased over time. They didn’t let the
stressors in the situation overcome them but rather acted to eliminate
the sources of their stress. In effect, they experienced the virtuous
circle of social identification represented in Figure 1a [PLEASE
DOWNLOAD THE PDF VERSION FOR THE FIGURE].
The contrast with the guards could not be greater. For them, lack of
social identification led to disagreement and discord. There was no
coordination amongst them, no leadership, no organisational
effectiveness. They worked against each other and thereby lost any
power they could have derived from the resources available to them.
Their inability to impose their will led to a decrease in group
identification and to rising levels of depression, burnout and internal
dissent over time. Rather than their roles and resources allowing them
to master the situation (and the prisoners), their lack
of identity allowed situational stressors to master them. In this way,
they were exposed to the vicious circle of social atomisation
represented in Figure 1b [SEE PDF VERSION].
Overall, these findings suggest that, far from undermining agency,
shared group identity provides the power that enables people to
implement their beliefs and values (Turner, 2005). Such collective
agency promotes the psychological well-being of individual group
members. As the days went by, the prisoners in our study became more
cohesive and powerful, while the guards became more fragmented and
powerless. This continued to the point where some prisoners broke out
of their cells and destroyed the old regime. Together, ex-guards and
ex-prisoners then proposed their own regime: ‘a self-governing,
The Commune: Power, group failure and health of societies
At its outset, the Commune exemplified all the advantages of a cohesive
group. This was no longer a category we had imposed upon our
participants, but rather one they had created for themselves. They
identified highly with the values and goals of the Commune and they
worked energetically to implement these goals. Indeed, initially they
worked harder and supported each other more than they ever had under
the old system.
However the Commune had a fatal flaw. While most participants supported
it, some did not. And while the ‘Communards’ were willing to be
self-organising they were unwilling to use power to discipline dissent.
As a result, the Commune system began to break down. Its supporters
became despondent as they became unable to turn their social beliefs
into a form of social being – or, in the terms used above, as the lack
of collective self-realisation became chronic. It was in this context
that those who opposed the Commune – a combination of ex-guards and
ex-prisoners – proposed reinstating the guard–prisoner system, but in a
more tyrannical form (see the manifesto, reproduced for the first time
on the contents page of this issue).
This was disturbing. But what was more troubling was that, as our
psychometric measures showed, those who had previously supported the
Commune were themselves becoming more authoritarian and more
sympathetic to autocratic leadership to the extent that they had
reached the same levels of authoritarianism as the dissenters. As a
result, those in the Commune showed limited resistance to the new
tyranny. This is where, for both ethical and practical reasons, we
terminated the study. So what started with our participants rejecting a
relatively mild form of inequality had ended on the brink of an
authoritarian world of their own making. How had this happened?
The crucial step is to recognise that social identities, and the norms
and values associated with them, are related to the practical ways we
organise our everyday world. Where they empower us to create the worlds
we value (as for the prisoners in the first phase of our study), they
engender positivity. Where we fail to use group power to organise our
world effectively (as for the Communards in the second phase), then
group beliefs become, quite literally, useless. So, because the
Communards remained suspicious of the exercise of group power, they
were unable to transform democratic ideals into working democratic
structures. As a result, these ideals came to seem more of a hindrance
than a help. By contrast, any system that promised to work – even a
tyranny that had previously seemed deeply unattractive – gained in
allure. The tragedy of the Communards was that their own fear of using
power created the conditions where power could be misused against them.
Giving choice not taking it away
For all the twists and turns in the BBC study, there are two findings
that are constant throughout. The first is that shared social identity
creates social power, and where people are willing to deploy that power
they become effective social agents who shape their own worlds. The
second is that where people are unable to shape their world – either
because they lack shared identity and hence power or because they have
shared identity but fail to deploy the power that flows from it – they
are liable to become despondent and open to alternative belief systems,
however extreme they might be.
Conceptually, this viewpoint is diametrically opposed to that which the
Stanford Prison Experiment is typically used to advance. Groups, we
suggest, give people choice rather than take it away. And the ability
to exercise choice is good for our well-being. How people exercise
their choice will depend upon the norms and values they subscribe to.
Hence the impact of groups upon the health of society is not given in
our psychology but is rather something for which people must take
responsibility. All members of a group, from the highest to the lowest,
play a part in determining what the group stands for and the type of
world it seeks to create.
Conversely, the failure of groups, and the consequent lack of
collective power, removes choice from people, and this is bad for the
well-being of individual members. It is also bad for the health of
society. For that is when people become more liable to accept extreme
suggestions and thereby succumb to inequitable solutions to their
social problems. That is when ordinary people and erstwhile democrats
can be seduced by tyranny.
In short, do groups and power corrupt? Not in and of themselves. But the failure
of groups does corrupt absolutely.
These are, of course, big and bold claims. We don’t expect everyone to
accept them without demur. Indeed Zimbardo (2006) himself remains
implacably opposed to our analysis. We have provided a detailed
response to his criticisms (Haslam & Reicher, 2006), but we welcome
the debate. Our major ambition in undertaking the BBC Prison Study was
to reopen normal scientific investigation and discussion around the
relationship between group processes and extreme behaviours. We have
put our data and our conclusions into the public domain and others can
now judge these for themselves (or, even better, advance the debate
through their own research).
As Turner (2006) notes in his commentary on our study, social
psychologists have been locked into a negative view of groups and a
narrow understanding of tyranny for far too long. As he points out, a
key and undeniable contribution of our study is that it encourages us
to ‘escape our theoretical prisons’ – forcing us to address new
questions and to look at old questions in new ways. As social
psychologists, clinical psychologists, organisational psychologists –
or even better, all together – it is high time to reconsider the
relationship between group processes, individual well-being and healthy
- Stephen Reicher is a professor of psychology at the University of St Andrews. E-mail: firstname.lastname@example.org.
- Alex Haslam is a professor of psychology at the University of Exeter.
BBC Prison Study official website: www.theexperiment.org.uk
Stanford Prison Experiment official website: www.prisonexp.org
Social science commentary on Abu Ghraib: tinyurl.com/8m2bx
Discuss and debate
Do people in groups inevitably abuse positions of power – and, if so, are they to blame?
Would society be healthier if we encouraged people to act as individuals, not as group members?
Should we seek to have an integrated understanding of social, clinical
and organisational psychology, and do we have the theoretical and
methodological tools to achieve this?
Have your say on these or other issues this article raises. E-mail
‘Letters’ on email@example.com or contribute to our forum via www.thepsychologist.org.uk.
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