People protest peacefully in China all the time.... Police try to contain the protests, as they would in any country and only use force to dispel them when it turns violent, again, as any police force anywhere in the world would do.
You're being disingenuous. You know that in China there is no (effective) right to protest. Police reserve the right to break up protests and arrest people who take part,
whether or not they turn violent. Some protests are tolerated, but if I or anyone else stood in the middle of Beijing or Lhasa with a sign saying "end one party rule, we need multi-party elections" I would be arrested very swiftly. Whereas in the UK, I'm free to wave a sign saying that the Conservative-Liberal Democrat coalition is bad for the UK and we need a new election.
And you obviously live in a different country to me if you can come out with a straight face to argue that people in the UK have the freedom to protest peacefully without fear of punishment.
Ever heard of the word 'kettling'?
Yes, I know about kettling, and I don't see that as punishment. It's not pleasant, but it's a temporary inconvenience. And it normally only happens when there is violence, it's not a default response to a protest.
For example, in 2002 the Countryside Alliance had around 400,000 people in London. There was no kettling then. Why? Because the protesters were peaceful.
Furthermore, the people who protested outside the police station after Mark D was shot were
not arrested or kettled. Why? Because they peaceful (at least at the start). If people continued to protest peacefully about the shooting or raised a different issue, but didn't resort to violence, there would have been little police action other than the usual monitoring of the situation.