Portland State University students hold an annual forum with the theme "Law and Disorder" at which they critique police conduct. Speakers tend to be people from the left who have a history of speaking out against police brutality.

This year, the forum couldn't get started because one of the speakers -- who has published numerous books and articles about the subject -- was shouted down by audience members who objected to some of his recent writing about sexual violence.

Kristian Williams, the panelist who was interrupted, was shouted at because of an essay he wrote last year in which he criticized what he saw as a pattern where those who are survivors of sexual violence are presumed to be the only ones who can talk about any conflict over a given incident.

His piece did not deny that sexual violence is real, but he questioned the way some people have been attacked as perpetrators. "Under this theory, the survivor, and the survivor alone, has the right to make demands, while the rest of us are duty-bound to enact sanctions without question," he wrote.

"One obvious implication is that all allegations are treated as fact. And often, specific allegations are not even necessary. It may be enough to characterize someone's behavior –– or even his fundamental character –– as 'sexist,' 'misogynist,' 'patriarchal,' 'silencing,' 'triggering,' 'unsafe,' or 'abusive.' And on the principle that bad does not allow for better or worse, all of these terms can be used more or less interchangeably. After all, the point is not really to make an accusation, which could be proved or disproved; the point is to offer a judgment. Thus it is possible for large groups of people to dislike and even punish some maligned person without even pretending to know what it is, specifically, he is supposed to have done. He has been 'called out' as a perpetrator; nothing else matters."

At last week's event, video of which appears on YouTube, Williams was shouted down and prevented from even getting a sentence out. Audience members repeatedly shouted: "We will not be silenced in the face of your violence." (Caution: Those offended by expletives may not want to watch the video of the event below.)

The video was shared on several conservative websites Monday. The three speakers -- who agreed that they had no choice but to call off the event -- issued a joint statement about the event, describing their inability to discuss the issues with the audience or to get enough quiet to proceed.

"We believe that the damage caused by patriarchy and intimate violence in our movements is a real and terrible force. These are problems that need to be discussed, addressed and confronted head on," the statement said. It added: "We also believe that our communities and movements are strongest when we can disagree without branding each other as enemies. Dialogue around critical issues is sometimes painful and complicated -- but it doesn’t have to mean that we destroy each other in the process, or that we sabotage other important work."

The statement also said that they made the decision to end the event when they heard that police were on their way to the event. "To be clear -- no one on the panel called the cops. And we also didn’t tell anyone else to call the cops." The statement praised organizers for sticking with the invitations, even as it became clear that Williams would be the subject of a protest.

Asked about the university's response to the event, Christopher Broderick, associate vice president for communications, said that he was not present, and so could not provide details on what happened. As to the general issues about a speaker being shouted down, he sent this statement by email: "Portland State is a large and diverse urban campus with nearly 29,000 students and scores of student groups who organize their own events. As a public university, PSU supports the free exchange of ideas inside and outside the classroom. Occasionally, a political event organized by students can get emotional, as this one did. If physical threats are made or if campus security is called, then the university responds to ensure a safe environment. That did not occur in this case. This was a student event, not a classroom or academic exchange, so it's the responsibility of the organizers and participants to determine how to work out their differences in a way that respects free speech."