By Ollie Gillman for Dailymail.com
This video shows the moment dozens of students encircled a Yale University official and screamed at him for sending an email telling them to ignore people dressed in offensive Halloween costumes.
Nicholas Christakis, the master of Silliman College at Yale, was surrounded after telling students to allow others to exercise free speech by wearing what they wanted on Halloween.
He was shouted down on Thursday as he tried to explain why he believed students should be able to wear what they want, with one young woman yelling at him and telling him to 'shut the f*** up'.
The email - sent by associate master Erika Christakis, Mr Christakis' wife - said: 'If you don't like a costume someone is wearing, look away, or tell them you are offended.
'Talk to each other. Free speech and the ability to tolerate offence are the hallmarks of a free and open society.'
However, some students saw this as a free pass for people to wear offensive costumes that could be seen as discriminatory.
One girl - seen in a video published by The Fire - launched into a expletive-ridden tirade at sociology professor Mr Christakis, who was trying to tell her why he felt the university should not censor what people wear...