The article goes over several. Off the top of my head: the supposed mental breakdown of Korpi (he was faking it), Zimbardo claiming he wasn't politically motiv

The article goes over several. Off the top of my head: the supposed mental breakdown of Korpi (he was faking it), Zimbardo claiming he wasn't politically motivated, Zimbardo claiming the students were free to leave at any time, Zimbardo lying or misleading as to what degree the 'guards' had been coached (specifically with regard to the role of Jaffe.) Details about each of these are available in the article.