What was a primary ethical concern raised about Zimbardo's study?

The primary ethical concern raised about Zimbardo's study revolves around the fact that the researcher did not intervene to stop the study when psychological harm was evident among participants. The experiment, designed to explore the psychological effects of perceived power in a simulated prison environment, led to significant distress and harmful behaviors among those involved. Despite the alarming consequences, Zimbardo allowed the study to continue for longer than was deemed ethical, putting the participants' welfare at risk.

This situation highlights the importance of the ethical principle of 'do no harm,' which is a fundamental tenet in psychological research. Researchers are obligated to protect participants from physical and psychological harm. The decision to prioritize the scientific investigation over the well-being of the participants raised significant ethical questions and calls for stricter adherence to ethical guidelines in psychological studies, especially regarding the duty of care researchers have to their participants.