Stop Republican interrupting judge (5)
I believe the answer is:
break
'stop' is the definition.
(I know that stop can be written as break)
'republican interrupting judge' is the wordplay.
'republican' becomes 'R' (abbreviation in US politics).
'interrupting' means one lot of letters goes inside another.
'judge' becomes 'beak' ().
'r' inserted into 'beak' is 'BREAK'.
(Other definitions for break that I've seen before include "Interrupt; holiday" , "Damage - interrupt" , "Holiday; snap" , "Fracture; holiday" , "Shatter; respite" .)