London police gets everyone an implement (6)
I believe the answer is:
mallet
'an implement' is the definition.
(mallet is a kind of implement)
'london police gets everyone' is the wordplay.
'london police' becomes 'met' (London Metropolitan Police).
'gets' means one lot of letters goes inside another (gets can mean captures or absorbs).
'everyone' becomes 'all' (I've seen this before).
'met' going around 'all' is 'MALLET'.
(Other definitions for mallet that I've seen before include "Hammer for pegs or croquet" , "Large hammer with wooden head" , "Wooden-headed hammer" , "An auctioneer's wooden hammer" , "Croquet stick" .)