Upset detective bust criminal without resistance (7)
I believe the answer is:
disturb
'upset' is the definition.
(I know that upset can be written as disturb)
'detective bust criminal without resistance' is the wordplay.
'detective' becomes 'di' (Detective Inspector abbreviation).
'criminal' indicates an anagram.
'without' is an insertion indicator ('without' can be similar in meaning to 'outside').
'resistance' becomes 'r' (electronics abbreviation).
'bust' with letters rearranged gives 'stub'.
'stub' going around 'r' is 'sturb'.
'di'+'sturb'='DISTURB'
(Other definitions for disturb that I've seen before include "Molest" , "Upset, confuse" , "Break" , "Interrupt; upset" , "Interrupt, annoy" .)