Expel from court detectives with cake (6)
I believe the answer is:
disbar
'expel from court' is the definition.
'detectives with cake' is the wordplay.
'detectives' becomes 'dis' (Detective Inspectors, DIs).
'with' is a charade indicator (letters next to each other).
'cake' becomes 'bar' (synonyms).
'dis'+'bar'='DISBAR'
(Other definitions for disbar that I've seen before include "Deprive barrister of the right to practise law" , "Disqualify from practising law" , "Deprive of the rights of a barrister" , "Braids (anag.)" , "Expel from the practice of law" .)