Conformity to social roles: Zimbardo's research

Emotionally stable participants were recruited and randomly assigned the roles of guard or prisoner.

The guards and prisoners had those roles only by chance. So their behaviour was due to the pressures of the situation and not thier personalities.

Control increases the study's internal validity. We can be more confident in drawing conclusions about the influences of social roles on behaviour. 

Banuazizi and Mohavedi suggest participants were play-acting. Their performances relfected streotypes of how prisoners and gaurds are supposed to behave. 

One guard based his role on a character from the film Cool Hand Luke. Prisoners rioted because they thought that is what real prisoners did.

But Zimbardo's data showed 90% of the prisoner' conversations were about prison life. The simulation seemed real to them, increasing the study's internal validity. 

(Fromm argues that Zimbardo understated dispositional influences)

Only a third of the guards behaved brutallly. Another third applied the rules fairly. The rest supported the prisoners, offering them cigarettes and reinstating privileges. 

Zimbardo's conclusion - that participants conformed to social roles - may be over-stated, exaggerating the power of the situation. 

The differences in the guards' behaviour show that they could exercise right and wrong choices, despite situational pressures to confrom to a role. 

Reicher and Haslam partially replicated the SPE, with different findings. Prisoners eventually took control.

Tajifel's social identity theory (SIT) explains this. Guards in the replication falied to develop shared social identity as a group, but prisoners did and refused to accept limits of their assigned roles.

So the brutality of the guards in the original SPE was due to a shared social identity as a cohesive group, rather than conformity to thier social roles. 

One issue arose because Zimbardo was both lead researcher and prison superintendent.

A student who wanted to leave the study spoke to Zimbardo, who responded as a superintendet worried about the running of his prison rather than as a reseracher.

This limited Zimbardo's ability to protect his participants from harm because his superintendent role conflicted with his researcher role.