Person put forward new rule in overbearing manner after taking sides (7)
I believe the answer is:
nominee
'person put forward' is the definition.
(I've seen this before)
'new rule in overbearing manner after taking sides' is the wordplay.
I cannot quite see how this works, but
'new' could be 'n' (abbreviation as in New Testament NT) and 'n' is found within the answer.
'in' is within the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for nominee that I've seen before include "Person standing for office" , "figure entering field?" , "Person proposed as candidate" , "No real owner" , "Chosen person" .)