You have a constitutional right to free speech - to a point; for instance, provided it does not inpinge on the rights of others, and/or does not endanger the public. This was a Q&A set up by an elected official who have every right to control it, for instance, limiting questions to one per person, limiting the time a questioner took, suggesting a questioner sit down and refrain from further speech if he/she wasn't satisfied with the answer, etc., etc. The individual in the audience very clearly attended the session with the intention of disrupting it. He intended to make a political statement before he asked any questions and he was repeatedly told to limit his disruptive activity. He clearly intended to create a further scene as they were attempting to remove him so that the event could continue, fighting against those trying to restrain him (police officers) and using a loud vice. He could have been charged with assault, resisting arrest, battery and other crimes.
I intensely dislike loudmouth motherfuckers like this who think the world resolves around them, who preach their rights while denying the rights of others. My only problem with this is the offices took FAR too long to remove them. If they would have clubbed the bastard I would have been more satisfied.