Range of a policeman in the South East (5)
I believe the answer is:
scope
'range' is the definition.
(I know that range can be written as scope)
'a policeman in the south east' is the wordplay.
'a policeman' becomes 'cop' (slang term).
'in the' indicates putting letters inside.
'south east' becomes 'SE' (abbreviation).
'cop' going into 'se' is 'SCOPE'.
'of' acts as a link.
(Other definitions for scope that I've seen before include "Range of action" , "Range of view" , "Charity" , "Extent; latitude" , "Space for movement or activity" .)