Why is a police constable referred to as a police officer in the UK

[Dom Tuk]

Is the police constable an officer grade? if a police constable were to visit/work in an army camp would they be allowed into the officers mess?. Why does the media refer to them as police officers?

[lady_p_gold]

Police constable is the starting rank of joining the police, so in answer to your question it is not the same as being an officer in HM Forces. So ... they would probably be 'allowed' in the officers mess as a guest if they visited an army camp, but as a guest .. in fact I am not sure of the protocol of visitors visiting army camps. I have been in the officers mess quite a few times and they still have very much of an 'establishment' air. I think the term has just become used as just a general term with a small 'o' and has got into everyday speech.

[Quizmonster]

The original meaning of the word, 'officer' was simply 'one who holds an office'...ie someone whose duty it is to perform a particular duty or function. Its application to a junior policeman dates back only to the 1890s.
It is not considered that makes him the equivalent of a commissioned officer in the British Armed Forces. There, the word 'officer', used alone, refers solely to someone who holds the Queen's Commission. Non-commissioned Officers...Corporals, Sergeants etc...are not called 'officers' unless the 'non-commissioned' part is added.
Police constables would certainly be allowed as invited guests in a military Officers' Mess, as would anyone else who had been invited by a member of that Mess.

[kempie]

An Officer is a person who holds office i.e has a particular responsibility for something. Constable is the title given to a holder of office within UK law enforcement.

Originally, in some European countries during the Middle Ages, a constable was a person in charge of keeping the horses of his lord. The title comes from the Latin comes stabuli (attendant of the stables).

http://en.wikipedia.org/wiki/Constable

[Grunty]

The preceding answers are correct. In addition, the phrase 'police officer' has replaced the word 'policeman' recently for reasons of discrimination. Although police officers of all ranks are technically constables, the word constable is also used to describe the lower rank. Thus the word 'officer' is useful to describe them all. Recently, the media have tended to use the term 'fire officers' to describe fire service personnel. Although the term is less clumsy than 'firefighters', it is really incorrect because they do not hold an office, such as the office of constable.