Outlaw's trial cut short (3)
I believe the answer is:
ban
'outlaw's' is the definition.
(banning is a kind of outlawing)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for ban that I've seen before include "Officially prohibit" , "Embargo" , "the calling of young vassals" , "outlaw" , "Veto" .)