Wrong to snare a politician (7)
I believe the answer is:
senator
'a politician' is the definition.
(senator is a kind of politician)
'wrong to snare' is the wordplay.
'wrong' indicates anagramming the letters.
'to'+'snare'='tosnare'
'tosnare' with letters rearranged gives 'SENATOR'.
(Other definitions for senator that I've seen before include "Member of upper US assembly" , "Member of upper house of legislature" , "Member of government" , "Roman politician" , "US legislator" .)