Have you considered that a lot of the trouble is often caused by violent police tactics?
And unfortunately the fact that they appear like this in the first place can provoke the trouble.
Both sides are to blame of course, hence why the 'ban' should be even handed, and the police also prosecuted when they remove their ID...
And the zeal with which protesters are tracked down and punished should be the same for the police who mete out indiscriminate beatings....
But it doesn't seem to work out that way does it, since the police have also been known to be able to kill with apparent impunity...