Unseats judge avoiding historic conflicts (5)
I believe the answer is:
ousts
'unseats' is the definition.
'judge avoiding historic conflicts' is the wordplay.
'judge' becomes 'j'.
'avoiding' indicates named letters should be taken away.
'historic conflicts' becomes 'jousts'.
'jousts' with 'j' taken away is 'OUSTS'.
(Other definitions for ousts that I've seen before include "Replaces" , "Forces out of position" , "Unseats, puts out of office" , "Supplants" , "Removes from office" .)