Actually the PC was following correct procedure.....
I quote section 11.1.7 of the Blackstones Police Operational handbook.
Section 11 GENERAL PATROL
11.1.7 Powers relating to anti-social behaviour
In the event of anti-social behaviour on a large scale, protection of the public must be considered a high priority straight after your own Health and Safety, your arrest record, the persecution of motorists (see sections 1,2,5,6,7,8,14,18,21 and 22) and the length of time until your next break.
You have the power to demand the member of the public be safe guarded in the following ways:
*Advise the member of public to stay in his/her home.
*Advise the member of public to seek a suitable refuge.(eg public toilets, Walls and shrubbery.)
*Advise the member of public to lie down and play dead.
If the member of the public fails to adhere to your instruction you have the power to arrest him/her for breach of the peace/and or anti-social behaviour.
11.1.7.5 Powers relating to anti-social behaviour
On Patrol be aware of people acting suspiciously EG:
*Hanging around public toilets
*Hiding behind walls
*Hiding behind shubbery
These people will often make an easy arrest and will increase your arrest record if you are down for the month, with very little risk of you encountering violence. Please remember for your own Health and Safety if someone looks a bit "nuts" it is better to leave him/her to it than risk confrontation.