Policed without cop - the type that's not working (4)
I believe the answer is:
idle
'not working' is the definition.
(I've seen this before)
'policed without cop the type' is the wordplay.
'without' suggests deleting specific letters.
'the type' is an anagram indicator.
'policed' with 'cop' removed is 'lied'.
'lied' is an anagram of 'IDLE'.
'that's' acts as a link.
(Other definitions for idle that I've seen before include "Monty Python team member" , "Unoccupied (time); run (engine) slowly" , "out of a job" , "having no effect" , "Circus entertainer" .)