Trigger warning: Girl gets arrested, seemingly for being Autistic in a built up area.

I'm still confused about what really happened or how the situation could have been handled.

1. The police were first involved in taking the drunken girl home from the city centre.  Why?  I thought the police were  no longer getting involved in mental health issues.
2. Why was the mother allowed to film the encounter on her mobile phone?  Any competent police person would have confiscated her phone and deleted the incriminating video.

Evidently they don’t consider drunken disorderly to be a mental health issue.

and seizing property without a lawful basis is a serious infraction for the police.

and even if they seize it deleting the video may simply not be possible if the phone is locked before they get a hold of it tthey have to take the defendant down to the station and threaten them with prosecution if they didn’t unlock the phone.

Again with the nebulous "threats".

What they gonna do if you still say no?

Especially if you say it very politely, explain why you have to regretfully say no, and STICK TO YOUR GUNS. 

I've been in way more trouble when I was touching my forleock and just "going along to get along" than when I've stood up for myself. But I am polite, I don't hate 'em I'm just fighting my own corner and doing what is right for me.

We don't live in a police state and a goodly amount of coppers are trying to do a good thing within the constraints placed upon them. But those like we see in that video they think we are their inferiors and they need to be disabused of that notion. 

Again with the nebulous "threats".

What they gonna do if you still say no?

Especially if you say it very politely, explain why you have to regretfully say no, and STICK TO YOUR GUNS. 

I've been in way more trouble when I was touching my forleock and just "going along to get along" than when I've stood up for myself. But I am polite, I don't hate 'em I'm just fighting my own corner and doing what is right for me.

We don't live in a police state and a goodly amount of coppers are trying to do a good thing within the constraints placed upon them. But those like we see in that video they think we are their inferiors and they need to be disabused of that notion. 

I Sperg said:

Especially if you say it very politely, explain why you have to regretfully say no, and STICK TO YOUR GUNS.

I have to agree 100% with this.

Inform yourself of your rights and stick to them.

There are unfortunately way too many police officers who are ignorant (willfully or otherwise) of peoples rights and I have seen too many cases when these have been trampled on by the police trying to get the outcome they want.

Always make sure you get the officers badge number and name when things look like they are getting sticky and if they are exceeding their remit then ask them to ensure their bodycam is recording and ask to speak to their supervisor as you believe the poilice officer is breaking the law with their requests.

And lawer up if they continue to trample over your rights - you are entitled to a free one if they decide to arrest you.