Quote Originally Posted by Gorgeous_Ginny
This link is all about the Metropolitan Police, which is basically the entire Police Force of England. LINK
That's not true. There isn't a "police force of England."

The Metropolitan Police (known as The Met) is a terretorial police force which only covers the Greater London area (this does not include the "City of London"), which is 32 London Boroughs. Anywhere other than Greater London the terretories are covered by other police forces. In total there are 39 police forces in England, 4 in Wales, 8 in Scotland and just 1 in Northern Ireland.

Also from my knowledge only uniformed officers wearing their hats can make an arrest because of the badge on them, or a uniformed officer has to be at the scene of the arrest with the un-uniformed officer, these are mainly field agents, detectives, etc.
This is a common misconception, due largely to TV crime shows not working with a police advisor to clear up in the mistakes. An officer is an officer regardless of what they are wearing (there are many who are often "out of uniform" be it for undercover/unmarked work or because their rank doesn't require them to).

The simple fact is that an officer of any rank can arrest anyone at any time whether on duty or not, wearing official police uniform or a pair of baggy jeans and an offensive t-shirt, so long as they produce their credentials (badge and warrant card) and advise you (in English) why you are being arrested. It's the warrant card that gives them the power to arrest you, not a uniform.

I've seen someone try and use this in court as a way of having the case dismissed (the arresting officer was undercover), and the judge had to stifle a laugh it was that ridiculous. Needless to say that person was found guilty and ended up in prison for 3 years.