The police has apologised over the arrest of the republican group

Apparently the police issued the apology partly as a result of public opinion, which is alarmed at the way the police behaved.

Those arrested were quietly released as there is no law covering the arrest.

This is not the way we or the police behave in the U.K. in spite of those thinking that we do and should. We have not yet become a fascist or authoritarian state.

Policing in the U.K. is by public consent, and that consent will be withdrawn if we have more instances like this.

The police know this and prefer to police by consent, then any other way.

However as I said I suspect their actions were not as a result of ignorant policing but an ignorant Home Office.

If people dont like living in a country where people are allowed to disagree with a monarchy there are plenty that require that kind of obedience.

WW I heard an interview with a top copper a couple of days ago (sorry, a bit vague I know) and he reckoned it was a mix of panic / over cautiousness and a relatively inexperienced workforce

I think republicans have the right to peaceful protest that doesn't disrupt everyone. If it is really disruptive, yes of course take action, but arresting people in advance in a democracy, "in case" is a frightening precedent.

‘I don’t know why people live in a country with a monarchy when there are so many without one’

And I don’t know where to start with that one!
Good heavens above!

Why would anyone go to a Coronation with placards if not to disrupt an occasion where people have slept out all night, coped with the rain, if not to try to ruin it. No one same would think that appropriate behaviour. Police should not have apologised, they should stick up against these militant embittered people.
Just say it's impossible now to keep law and order because of people like that. You can't have it both ways. I don't know why people live in a country with a monarchy when there are so many others without one, they just want trouble.