Psychologist behind the controversial 'Stanford Prison Experiment' dies at 91

The study was ended after six days as the students playing guards became psychologically, according to the Stanford statement

SAN FRANCISCO (AP) — Philip G. Zimbardo, the psychologist behind the controversial “Stanford Prison Experiment” that was intended to examine the psychological experiences of imprisonment, has died. He was 91.

Stanford University announced Friday that Zimbardo died Oct. 14 at his home in San Francisco. A cause of death was not provided.

In the 1971 prison study, Zimbardo and a team of graduate students recruited college-aged males to spend two weeks in a mock prison in the basement of a building on the Stanford campus.