Draw Back for detective's benefit (12)
I believe the answer is:
disadvantage
'draw back' is the definition.
Although both the answer and definition are verbs in their base form, I don't see how they can define each other.
'detective's benefit' is the wordplay.
'detective's' becomes 'dis' (Detective Inspector).
'benefit' becomes 'advantage' (I've seen this before).
'dis'+'advantage'='DISADVANTAGE'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for disadvantage that I've seen before include "Drawback" , "Downside" , "Catch" , "Flaw -- weak point" , "Handicap" .)