Either way it is their right to critique what they see and fight for changes where they see they need to be made. As with every freedom, there are limits. If they simply seek to influence the democratic process, that is their right. If they seek to circumvent that process by violent means, or means which infringe upon the rights of others, they are not within their rights. I'm curious, is the only prescribed way of changing the constitution adding amendments? Can the constitution itself be changed? Adding Amendments is only neccessary when you're changing the Constitution. The two are one and the same.