Zimbardo conducted the Stanford Prison Experiment (1971) to investigate how individuals conform to social roles
He recruited 24 male university students who were deemed psychologically stable and randomly assigned them to the role of either prisoner or guard.
The study took place in a mock prison in the basement of Stanford University.
Prisoners were arrested at their homes, stripped, deloused, and given uniforms with ID numbers, while guards were provided with uniforms, reflective sunglasses, and batons.
The guards were instructed to maintain order but were given no specific training.
The experiment was planned to last two weeks but was terminated after just six days due to the extreme distress experienced by the prisoners and the increasingly abusive behavior of the guards.
A key strength of Zimbardo’s study is its high level of internal validity.
The controlled environment ensured that participant behavior was influenced by their assigned social roles rather than individual personality differences
Participants were randomly assigned to roles, minimizing pre-existing differences as a confounding variable.
This suggests that the observed behaviors, such as the guards' aggression and the prisoners' submission, were due to the power of situational factors rather than dispositional traits.
However, a major weakness of the study is its ethicalissues, particularly regarding protection from harm
Many participants experienced severe emotional distress, with some prisoners suffering breakdowns
Zimbardo, acting as the prison superintendent, failed to intervene early enough, raising concerns about researcher responsibility
Although participants gave informed consent, they were subjected to extreme psychological pressure, bringing into question whether the study adhered to ethical guidelines
This limits the study’s credibility and raises concerns about the balance between scientific research and participant welfare.