Gather poor policeman must go without an ... (7)
I believe the answer is:
compile
'gather' is the definition.
(I've seen this in another clue)
'poor policeman must go without an' is the wordplay.
'poor' indicates anagramming the letters.
'must go without' indicates named letters should be taken away.
'policeman' with 'an' removed is 'policem'.
'policem' anagrammed gives 'COMPILE'.
(Other definitions for compile that I've seen before include "Polemic (anag.)" , "Marshal" , "Assemble (a collection)" , "Put together" .)