The Stanford prison experiment was a psychological study conducted in 1971 by Philip Zimbardo and his colleagues at Stanford University. The experiment aimed to investigate the psychological effects of becoming a prisoner or prison guard. While the study yielded important insights into human behavior, it has become infamous for its highly unethical methodology. Here is an in-depth look at why the Stanford prison experiment is considered so unethical.
The Study Design Was Highly Deceptive
One of the main criticisms of the Stanford prison experiment is that the study design involved significant deception of the participants. The recruitment ad described the study as lasting two weeks and only vaguely hinted that participants may be asked to take on a prison-like role:
“Male college students needed for psychological study of prison life. $15 per day for 1-2 weeks beginning Aug. 14.”
The real aim of the study was not disclosed to participants upfront. After being selected, participants were assigned to be either “prisoners” or “guards” without their knowledge or consent. This deception about the true nature of the study likely impacted how participants behaved during the experiment.
Participants Did Not Give Informed Consent
Closely tied to the deception issue is the fact that the Stanford prison experiment did not obtain informed consent from its participants. The recruits were not fully briefed about what the study would entail before agreeing to participate.
The experiment lasted 6 days rather than the advertised 1-2 weeks, further violating the consent given. When the participants playing prisoners objected to the conditions, they were not allowed to quit the experiment as they believed they should be able to based on the initial advertisement.
Participants Were Distressed and Traumatized
The Stanford prison experiment has been criticized for causing significant psychological distress and trauma in participants playing prisoners. The “prisoners” were unexpectedly arrested, stripped naked, deloused, chained, and locked in cells.
Guards frequently berated them and enacted arbitrary “punishments” like removing their mattresses. Several prisoners experienced emotional breakdowns and had to be released early from the study. Zimbardo himself admitted the experiment was “madness” for the prisoners.
Unethical Interactions Were Allowed to Continue
Critics condemned principal investigator Philip Zimbardo for allowing the experiment’s unethical interactions to escalate instead of putting a stop to them. As the lead researcher, Zimbardo had a responsibility to ensure the wellbeing of his participants.
However, Zimbardo got caught up in the experiment himself and did little to prevent the distressing treatment enacted by the guards. He also did not allow prisoners to quit the study as they should have been able to.
The Guards Quickly Conformed to Their Roles
Within 36 hours, the guards had settled into their roles and began enacting increasingly cruel and dehumanizing punishments. They verbally harassed the prisoners, carried out arbitrary punishments like making prisoners do push ups, and wake them up for counts every hour.
Critics argued that Zimbardo encouraged the guards’ negative behavior either explicitly or implicitly through lack of interference. The conformity effect observed has been used to explain atrocities committed by those merely “following orders” in contexts like war.
The Study Lacked External Oversight
The Stanford prison experiment lacked appropriate external oversight to match its risky human-subject study design. The study also took place during a time before stringent ethics standards for experiments were in place.
Zimbardo and his colleagues acted as both experimenters and ethics committee, introducing bias. Modern standards would require independent ethics reviews and check-ins during an experiment this psychologically intense.
The Sample Was Too Small to Generalize
While the Stanford prison experiment is often discussed as demonstrating truths about human nature, the sample of 21 white middle class male participants makes it impossible to generalize the findings more broadly. Participants were selected deliberately to be homogenous and healthy to isolate the psychological effects of becoming a “prisoner” or “guard.”
However, the lack of diversity among participants means the results cannot necessarily be extended to people of different ages, genders, races, nationalities, socioeconomic status, education levels, and mental health backgrounds.
There Are Concerns AboutDemand Characteristics
Some psychologists have suggested that the shocking negative behaviors observed in the Stanford prison experiment were at least partially due to demand characteristics.
Demand characteristics refer to cues that make subjects aware of what the experimenter expects to find or how they are expected to behave. The prison-like environment may have cued the participants to act out their stereotyped roles as cruel guards or helpless prisoners.
The Experiment Could Not Be Replicated Today
Modern ethics standards would prohibit replicating the Stanford prison experiment today in any close capacity. Since revealing the real purpose of the study upfront would influence results, deceiving participants the way Zimbardo did would not be allowed.
Subjecting participants to even mild distress, let alone trauma, without their consent would also never be approved by an institutional review board. This makes the study impossible to replicate and the results unverifiable.
Concerns About Scientific Oversight
Beyond ethics concerns, the Stanford prison experiment has been questioned for its scientific rigor and oversight. Some scientists argue there were fundamental methodological problems with the study’s design, execution, and analysis.
Critics point to a lack of concrete rules governing the guards’ behavior, no control group, and researcher bias in interpreting the results. Some say the findings were exaggerated, particularly the notions that participants completely internalized their roles and that the prison situation had no influence on behavior.
The Results Cannot Be Separated From Ethics Concerns
At its core, the major criticism leveled against the Stanford prison experiment is that the unethical treatment of participants invalidates any results or conclusions drawn from the study.
Researchers have an ethical responsibility to avoid harming subjects that supersedes the goal of achieving scientific knowledge. Ultimately, the ends do not justify the means when it comes to unethical research practices. Any data gathered through deceiving, psychologically distressing, or traumatizing participants cannot be considered scientifically valid.
Key Takeaways From the Stanford Prison Experiment:
- The study involved significant deception, lack of informed consent, and psychological harm to participants.
- Prisoner participants experienced distress and traumatization, while guards quickly conformed to their roles.
- Principal investigator Philip Zimbardo failed to prevent unethical treatment from escalating.
- The study lacked sufficient external oversight and safeguards for human subjects.
- There are concerns about sample size, demand characteristics, scientific rigor, and ability to replicate the experiment.
- The unethical methodology undermines any research findings or conclusions drawn.
Why Do Some Defend the Study Despite Ethics Concerns?
Despite the significant ethics violations, some scientists have argued the Stanford prison experiment was ethically justified because of the valuable insights gained. They contend that the ends justified the means. However, most modern psychologists reject this notion and agree the experiment went too far in harming participants. Here are some key points on both sides of the debate:
- Zimbardo argued the study revealed important truths about human behavior relevant to improving society and preventing tragedies.
- Defenders claim strict ethics standards stifle research progress and that no lasting harm was done.
- Critics counter that human dignity and rights should never be sacrificed for science. The prisoners’ distress was real and not worth any gain in knowledge.
- Zimbardo’s failure to act as soon-to-be President of the APA at the time undermines his ethical defense. He had a duty to stop unethical treatment as the lead researcher.
- There are still means of studying conformity and prison environments ethically such as interviews, surveys, and open-ended studies. Unethical treatments are never necessary.
Conclusion: The Stanford Prison Experiment Provides a Cautionary Tale
Ultimately, the Stanford prison experiment is widely regarded today as both unscientific and unethical. While it aimed to better understand human behavior, its methodology caused unacceptable human distress and harm.
The study provides an important historical example of why strong ethical safeguards and independent oversight are essential when conducting human subjects research, especially experiments that could potentially compromise wellbeing.
Psychologists today can learn valuable lessons from the Stanford prison experiment when designing their own studies. Above all, respecting human dignity and the principle of “do no harm” must take precedence over achieving results. With careful methodology and ethics oversight, psychologists can work to advance knowledge of human behavior ethically and responsibly.