Zimbardo – Conformity to social roles

• Strengths of the SPE


  • Zimbardo had high control over certain variables such as the selection of participants
  • Zimbardo randomly allocated participants to the role of prisoner or guard which increases the internal validity of his study and strengthens his procedure and provides good support for his theory that individuals do conform to social roles
• Weaknesses of the SPE


  • The problem of demand characteristics - participants may have guessed the aim of the study and acted in the way they thought the experimenter would want
  • One guard deliberately 'played' his role based on a prison guard in the film 'Cool Hand Luke', suggesting conformity was to please the experimenter not real conformity to social roles
  • Many ethical issues - participants were not protected from psychological harm, with one participant suffering such acute anxiety that they asked to be released, and participants were humiliated when instructed to complete dehumanising tasks
• Similarities between guard behaviour in the SPE and the dehumanising and violent behaviour by the US military police towards Iraqi prisoners at Abu Ghraib


  Suggests there is external validity to Zimbardo's study as there are real life examples of such behaviour
• Not all guards behaved brutally in the SPE, suggesting individual differences are important
• Some guards were tough but fair; some were brutal yet others rarely exerted control over the prisoners. Some were even considered 'good guards' and did the prisoners small favours
• This suggests that situational factors may only influence the behaviour of certain individuals, meaning situational factors are a stronger influence for some individuals and dispositional factors affect others more greatly
• It demonstrates the choice that some guards made to behave in the way they did