http://www.indymedia.org.uk/en/2010/08/456677.html

Write to the police today and tell them what a good little boy/girl you are and that you're really well behaved.

You could contact the National Coordinator of Domestic Extremism one ACC Anton Setchell under the Data Protection Act, answer some questions and send a tenner. However I would urge extreme caution if you do not think you are known because you will be GIVING them inf'o' about yourself so they can search for your file. My advice is to try and stay anonymous and don't worry about it, it is highy unlikely that this will affect your life but it is of course your decision, if you want to pursue this good luck, if they do have a file on you contact FITWATCH, go to the press. The police just like information about people it makes them feel in control

You are not obliged to give your name and address to the police unless you are:
1. driving a motor vehicle
2. they want to send you a summons for a minor offence
3.when you are arrested, they simply won't release you until they find out who you are, unless they decide you are a complete innocent.
4 section 50 police reform act if they suspect that you are behaving in an anti social way. Peacefully protesting is responsible citizenship not "anti social" so tell them to fuck off if they try it and you really have just been standing about with a placard. They use section 50 a lot and I have been arrested twice for refusing details won my case and sued for £12,500 so it is worth standing your ground.

Don't worry about snide comments from other activists, some are a bit long in the tooth, cynical and grumpy forgetting that maybe other people, especially new people are nervous of the state and the consequences of questioning state power.

As it has come to light this week that other activists who are new have accepted cautions can I point out that this is usually a really bad idea. A caution is in law an admission of guilt for a criminal offence. It stays with you for life and has to be mentioned on any job application exempt from the Rehabilitation of Offenders Act i.e any work with children or vulnerable adults and quite possibly banking etc. Many people just think it is a paper exercise and that it is a way of getting out of the cells. NO it is a way for the police to get a result for a case that they would have to otherwise drop as they have no evidence. Don't say anything to the police either apart from basics regarding custody, say nothing about the alleged offence, say nothing in interview, safest way.

they are off your file/CRB check after 5 years.

They are still relevant if you want to become a doctor, nurse, a care assistant, a special needs worker, a teacher etc and for certain types of voluntary work. In that sense they are with you for life and have to be declared. People going to the US and Canada now have to state whether or not they have ever been arrested let alone accepted a caution.
5 years is a long time to have to wait for a time when you can omit mention of a caution for stacking shelves. Who is an employer going to go for? Someone with a caution? Someone without? Of course ideally working for shitty company is not ideal anyway but sometimes people might need paid work/go abroad. A caution can interfere with that

If the police offer you a caution it's likely they don't have enough evidence to charge you with, or that they wouldn't consider it worthwhile to do so.

Write to the Chief Constable of the force, stating your concerns and give as much detail as possible about the circumstances, the cop's number, the date time and place etc.

Put in your letter that you are concerned about how this may affect your employment prospects and ask where you can find out the details of the report the cop made and the spotter card.

You can also put in Data Protection Act 1998, requests to the local police, and the National Public Order Intelligence Unit at New Scotland Yard which is where this stuff is held.
If you do then ask for ALL the information they have on you, including pictures, emails letters etc and the details of the incident you describe should be on this too.
You do have to supply them with a photograph, 10 quid and proof of your identity, an NHS card is sufficient.

 http://www.ico.gov.uk/for_the_public.aspx

A caution can not be imposed on you. I is technically your voluntary admission of guilt.

The truth is that most people would rather sign an admission of committing some "offense" or other and be "let off" quick than face the punishment being put through a trial. The police force is very manipulative.

"If the police offer you a caution it's likely they don't have enough evidence to charge you with, or that they wouldn't consider it worthwhile to do so."

evidence for a caution is the same for a charge (PACE). There are thing called "chargeing standards" this also means that a caution can be offered, it is NOT as Lynn said a criminal conviction, it is a police warning and is only admisable if wanting to work with children or vulnerable people (SWP;), unless of couse Lynn likes the idea of some nasty but cautionable people working with children?

I did not say that a caution was a conviction but it will pop up on an enhanced CRB check.
Lots of people have no convictions or cautions but have still raped and molested children, whether or not someone has a criminal record/a caution is not a good way of determining character. Some of the greatest characters in history were "criminals", the suffragettes, Ghandi, Martin Luther King.. . It is a matter of fact not opinion that cautions have to be declared in certain situations for life and my concern is that activists are accepting them without realising the consequences.