Very correct answer in you post. But if a citizen believes the hearings in question are extra-constitutional, does he have the “right” to intrude, say his words and be arrested? Just askin.
He has a right to file charges pursuant to due process.
He has a right to inform others of his view, in an appropriate forum.
Remember: sometimes our side holds hearings which the other side “believes are extra-constitutional” - do you approve of them disrupting such hearings? or do you want them to use the plethora of orderly means thereto, indicated by “Congress shall make no law ... abridging ... the right of the people peaceably to ... petition the government for a redress of grievances”? What this guy did was not “peaceable”.