@Demosthenes49
“Why can’t CMC say that protesting interferes with their ability to bring speakers onto campus, which is a regular activity, cite evidence of cancelled speakers, and thereby prohibit protest? While permissible in a private institution, I think there would be a serious vagueness problem for a state school.”
Why not? Bc they have other options that do not completely disallow free speech. (If they had NO other options, it might even be permissible, i.e., no loud protesting outside an exam site). Unless and until the school interprets it “over the line”, a bit of vagueness is not really a problem.