There was no violation of his free speech rights. Free speech can be controlled by content (rarely) and conduct (time, place, and manner). In places like state schools restrictions to conduct must be "viewpoint neutral and they have to be reasonably related to a legitimate government purpose."

He can't prove they did it because of his political beliefs. No (audible) mention was made of him being a "little commie puke", etc.

And because this is a state school the state's interests here are the school's interests. The school's interest is to have a productive educational environment. Listening to one guy rant and rave and take more time than he should makes the environment unproductive for the other students.

Once the kid resisted arrest he asked for trouble. "Don't taze me bro!" Well then, shut up.