zimbardo

zimbardo

• wanted a more dynamic social psychology experiment than Asch or Milgram:

  • more interaction, participants, duration

• challenged the ‘bad apple’ theory - belief that tyranny comes from individual personality (eg authoritarianism)

• instead, wanted to test the situations power to corrupt - ‘bad barrel’ hypothesis

context: US prisons in the 1970s

• reports of violence, abuse and riots

• social concern about institutional cruelty

• inspired the stimulated prison study

The Stanford Prison Experiment

participants

• ad placed for volunteers for a study on ‘prison life’

• 70 applied →24 selected: healthy, middle class males

• paid $15 per day

• randomly assigned: 12 guards, 12 prisoners

the prison set up

• conducted in the Stanford University basement

• designed with:

  • steel-bar cells

  • ‘the hole’ = solitary confinement

  • hidden cameras and microphones

  • no clocks/windows (disoriented time)

study procedure (day by day)

DAY 1:

• prisoners were stripped, searched, dehumanised (IDS, ankle chains)

• guards wore uniforms/sunglasses; created their own rules

DAY 2:

• prisoner rebellion →guards respond with:

  • harassment, intimidation

  • solitary confinement

  • divide and conquer; privileges to compliant prisoners

DAY 3-6

• prisoner releases: due to extreme distress, breakdowns

• visitors allowed under surveillance

• mass escape plot suspected

• hunger strike

• priest visit and parole board

• study terminated on day 6 (planned for 2 weeks)

key observations

• no training needed - guards naturally adopted cruel roles

• uniform and role = abuse of power

• aligns with ‘banality of evil’ - ordinary people commit atrocities under certain conditions

conclusions

• deindividuation: loss of identity and morals

• situational forces → tyranny, not inherent traits

• demonstrated how systems can corrupt

debate and controversy

ethical issues

• distress: breakdowns in prisoners, upset parents

• right to withdraw: often dismissed

• manipulation: zimbardo deflected blame onto parents

scientific validity

• zimbardo briefed guards with instructions to create fear, powerlessness and loss of freedom

• critics argued guards were coached, not spontaneously cruel

key critiques

role vs identity

• haslam and reicher: guards didn’t blindly confrom; acted based on shared identity

• Bartels: ‘stanford orientation’ encouraged expected cruelty

• Blum: one prisoner faked a breakdown to study for exams - but later contradicted his own story

participant bias

• ad for a prison study attracted more aggressive, narcissistic people

theoretical debate

• self categorization theory: people don’t adopt roles blindly - they internalise roles as part of group identity

empirical weakness

• SPE was never published in a peer reviewed journal

• lacked transparency, data scrutiny

BBC prison study (2001) - Haslam and Reicher

study setup

• simulated prison, 15 men (5 guards, 10 prisoners)

• aimed to study by tyranny and resistance

• focus: social identity theory

findings

• guards did not automatically act cruel

• resistance increased when prisoners shared identity

• tyranny arose from powerlessness, not role

zimbardos response

• dismissed BBC study as reality TV

• criticised the planned intervention

impact and legacy

real-world relevance

• US prions: zimbardo believed conditions worsened after SPE

• referenced in cases like Abu Ghrabib (Iraq prison abuse)

• inspired ‘the lucifer effect’ (zimbardo, 2007)

cultural impact

• two movies

• referenced in military training, ethics courses

• became a symbol of how power can corrupt

final takeaways

• SPE shows how situational forces can lead ordinary people to commit extraordinary cruelty

• sparked major debates on:

  • role of conformity vs identity

  • ethics in research

  • the psychology of power and oppression