Spiritual mentor to leave police department reeling with a hire fee (9)
I believe the answer is:
godparent
'fee' is the definition.
Although both the answer and definition are singular nouns, I can't understand how one could define the other.
'spiritual mentor to leave police department reeling with a hire' is the wordplay.
'spiritual mentor' becomes 'go' (I can't justify this - if you can you should believe this answer much more).
'to leave' indicates taking the first letters (I've seen 'left of' mean this (the leftmost letter in the word)).
'reeling with' indicates anagramming the letters.
'hire' becomes 'rent' (synonyms).
The initial letters of 'police department' is 'pd'.
'pd' with its letters anagrammed with 'a' can make 'dpa'.
'go'+'dpa'+'rent'='GODPARENT'
Can you help me to learn more?
(Other definitions for godparent that I've seen before include "Religious guardian" , "Pet dragon (anag)" , "Baptism sponsor" , "as one responsible for charge" .)