What happened in the basement of the psych building 40 years ago shocked the world. How do the guards, prisoners and researchers in the Stanford Prison Experiment feel about it now?
It began with an ad in the classifieds.
Male college students needed for psychological study of prison life. $15 per day for 1-2 weeks. More than 70 people volunteered to take part in the study, to be conducted in a fake prison housed inside Jordan Hall, on Stanford’s Main Quad. The leader of the study was 38-year-old psychology professor Philip Zimbardo. He and his fellow researchers selected 24 applicants and randomly assigned each to be a prisoner or a guard.
Zimbardo encouraged the guards to think of themselves as actual guards in a real prison. He made clear that prisoners could not be physically harmed, but said the guards should try to create an atmosphere in which the prisoners felt “powerless.”
The study began on Sunday, August 17, 1971. But no one knew what, exactly, they were getting into.
Forty years later, the Stanford Prison Experiment remains among the most notable—and notorious—research projects ever carried out at the University. For six days, half the study’s participants endured cruel and dehumanizing abuse at the hands of their peers. At various times, they were taunted, stripped naked, deprived of sleep and forced to use plastic buckets as toilets. Some of them rebelled violently; others became hysterical or withdrew into despair. As the situation descended into chaos, the researchers stood by and watched—until one of their colleagues finally spoke out.
The public’s fascination with the SPE and its implications—the notion, as Zimbardo says, “that these ordinary college students could do such terrible things when caught in that situation”—brought Zimbardo international renown. It also provoked criticism from other researchers, who questioned the ethics of subjecting student volunteers to such extreme emotional trauma. The study had been approved by Stanford’s Human Subjects Research Committee, and Zimbardo says that “neither they nor we could have imagined” that the guards would treat the prisoners so inhumanely.
In 1973, an investigation by the American Psychological Association concluded that the prison study had satisfied the profession’s existing ethical standards. But in subsequent years, those guidelines were revised to prohibit human-subject simulations modeled on the SPE. “No behavioral research that puts people in that kind of setting can ever be done again in America,” Zimbardo says.
The Stanford Prison Experiment became the subject of numerous books and documentaries, a feature film and the name of at least one punk band. In the last decade, after the revelations of abuses committed by U.S. military and intelligence personnel at prisons in Iraq and Afghanistan, the SPE provided lessons in how good people placed in adverse conditions can act barbarically.
The experiment is still a source of controversy and contention—even among those who took part in it. Here, in their own words, some of the key players in the drama reflect on their roles and how those six days in August changed their lives.