Sorry to say it: she is a victim of misbehaviour, resistance against administrative orders, and her faith, that would be tolerated. To my knowledge Ms O'Brien is well-known among the protesters and the police so something might piled up. And: yes, I do support a zero tolerance policy.
Actually most participants in civil disobedience against authoritarian regimes do so in the knowledge that it can have consequences like this. As you can see from the video, the police officers violent assault doesn't surprise her at all. You've misunderstood what the term 'zero tolerance' means.
I absolutely respect your right to think so.