I am of the belief that, in the UK, the majority of Police pilots are ex-military, albeit that they are regarded as "civvie".
As of last summer, full time Police helicopter pilots were made up as follows:
Ex Military: 97. Civilian(ie not Ex Mil) 22, of which I think 2 were ladies.
The ex Mil were split as follows: Army 56, RAF 11, RN 19, Royal Marine 11.
The numbers only include those employed fulltime at units, and not floaters/relieve pilots.