Here's a report from a cancelled debate from last February sponsored by the Oregon State Socratic Club:
We are sorry to have to inform you that the debate on Thursday, February 25th on the topic "Is Gender a Choice?" has been canceled. Our debaters were informed that some students on campus are offended by the topic of the debate and may plan to protest the event as transphobic, despite the fact that we had both sides fully represented. Because of this one of our speakers did not feel comfortable proceeding with the event. We are disappointed, but understand.
We hope you'll keep up to date with us as we continue onward.
The idea seems to be that the mere presentation of both sides of some issues is considered offensive.