Bats your are talking bolloks.
"Finally, I should add that there is no statutory power for the police to require someone to "stop and account" for themselves, but the police can and do frequently do so. The police are entitled to ask you what you are up to, but unless they exercise their further powers of stop and search or arrest you, you are entitled to walk away – though please see our first advice clinic piece when we advised that it might be sensible to confirm your basic details.
If the police do stop and ask you to account for your presence in a place, you do not have do provide any personal details and the police must, according to the codes, make a record of your ethnicity."