This may be because criminal, with fake emotion, takes in judge (11)
I believe the answer is:
conjunction
'this may be because' is the definition.
('because' is a conjunction)
'criminal with fake emotion takes in judge' is the wordplay.
'criminal' becomes 'con' (abbreviation for 'convict').
'with' says to put letters next to each other.
'fake emotion' becomes 'unction' (unction can mean insincere emotion).
'takes in' is an insertion indicator.
'judge' becomes 'j' (abbreviation for judge).
'con'+'unction'='conunction'
'conunction' placed around 'j' is 'CONJUNCTION'.
(Other definitions for conjunction that I've seen before include "'And' is one" , "Part of speech - astronomical coincidence" .)