Bar traitor, criminal and judge? (10)
I believe the answer is:
arbitrator
'judge?' is the definition.
(I know that arbitrator is a type of evaluator)
'bar traitor criminal' is the wordplay.
'criminal' indicates an anagram.
'bar'+'traitor'='bartraitor'
'bartraitor' with letters rearranged gives 'ARBITRATOR'.
'and' acts as a link.
(Other definitions for arbitrator that I've seen before include "Independent settler of dispute" , "Someone chosen to settle a dispute" , "Judge" , "referee" , "Umpire" .)