Former Vermont Gov. Howard Dean suggested on Twitter that the First Amendment doesn’t protect conservative commentator Ann Coulter.In California this is true, in fact the entire US Constitution is ignored out here.
But, in general, where the US Constitution applies, the rule is that free speech is allowed whenever open speech is allowed. The public universities are considered places of open speech, they have talking and lecture series already available for use and free speech is expected.
But certain speech is evidence of crime and likely to get you arrested. We shouldn't yell fire in a theater, but we can yell popcorn. The former is evidence of attempted public mayhem, simply delivered by free speech. You are arrested for mayhem, not speech.