Was it science, or performance art?

After the horrors of the Holocaust and World War 2, the field of social psychology was dominated by a need to understand what made ordinary people become monsters and allow themselves to be hypnotised by the murderous directives of maniacal psychopathic leaders. In the 1960s, Stanley Milgram, a Yale University professor influenced by the revelations of the trial of Nazi Adolf Eichman, conducted a controversial experiment to show how far those taking orders would go in service of the directives of their superiors. Subjects assigned the role of teachers to invisible students were ordered to administer increasingly dangerous levels of electric shocks and, despite some qualms, nearly all did as they were told. Milgram’s work was later used to explain the horrific events of the Mai Lai massacre, which took place during the Vietnam War in 1968, and saw US soldiers massacre unarmed women and children in a South Vietnamese village.

Milgram’s work inspired other social psychologists to go to extraordinary measures to investigate similar behaviours, none more so than Stanford Professor Phillip Zimbardo, who, in 1971, placed an advert in local newspapers seeking male students to participate in an experiment simulating and investigating prison life. They'd be paid $15 a day and expected to play their roles for two weeks. Twelve participants were assigned the roles of prison guards to oversee 10 prisoners and, as Zimbardo would later reveal, the increasingly sadistic behaviour of the guards was such that, when the good doctor’s girlfriend beseeched him to stop the madness, he was forced to end the experiment on day six.

Just as the real-world events of Mai Lai had brought wide public attention to the work of Milgram, the real-world tragedy of the Attica prison riot in September 1971, the deadliest in US history, placed Zimbardo’s research in the public consciousness, where it would remain for the next half a century.

The Stanford prison experiment has been cited as a groundbreaking study demonstrating how environment can influence the actions of people so that they become unrecognisable monsters. In 2004, when the world was shocked by the images of torture and humiliation meted out by US soldiers to Iraqi detainees at the Abu Ghraib prison, Zimbardo was on the screens of the world’s news channels to explain how nice, good ol' young American men and women had become gleefully immoral sadists, and even defended one of them during his trial.

The experiment was fodder for several feature films, a television series and a slew of documentaries that have mostly viewed it with a morbid but validating curiosity.

Now, director Juliette Eisner has produced a three-part docuseries for National Geographic, which, through interviews with surviving participants; critics of Zimbardo’s methods; and a final interview with Zimbardo (conducted before his death last year at the age of 91) casts incredulous light on the Stanford prison experiment. It suggests that perhaps it’s best viewed not as a rigorous scientific investigation but as a haphazard dark piece of performance theatre manipulated towards its outcome by significant interference and omissions on the part of its fame-hungry overseer.

After an initial episode, which recounts through interviews with participants the six days of the experiment, the series switches gear in the second episode. We're introduced to dogged French researcher Thibault le Texier, whose investigation of the full archive of the project resulted in a book published in French in 2019 (translated into English), which methodically debunks Zimbardo’s myth making, casting doubt on the validity of his findings.

Without giving everything away, it’s enough to say that le Texier makes a compelling case for re-evaluating the 20th century’s most famous psychological study and take its revelations with a pinch of salt. His criticisms are supported by the views of the participants themselves who, after half-a-decade of interviews and media attention, are given the space to reflect on their experiences without Zimbardo's guiding hand. 

Zimbardo’s interview gives insight into his personal background and shows him to be not such a scientific genius as a fallible mortal driven by past traumas and experiences towards personal success, public adulation and attention.

The experiment that was supposed to be a neutral investigation into the circumstances that bring out the worst in human nature seems more influenced by the psychologies of those who conducted it and who participated in it. The SEP — as it’s become known — might be less scientific investigation and more improvisational theatre exercise gone awry.

If it doesn’t hold up, the questions it provided answers to remain depressingly inexplicable. In the era of Donald Trump and the January 6 rioters, that's terrifying.

• The Stanford Prison Experiment: Unlocking the Truth airs on National Geographic (DStv channel 181) from Sunday June 15 at 9pm.