Cancel right to go in peace (5)
I believe the answer is:
erase
'cancel' is the definition.
(erasing is a kind of cancelling)
'right to go in peace' is the wordplay.
'right' becomes 'r' (common abbreviation).
'to go in' indicates putting letters inside.
'peace' becomes 'ease' (I've seen this in other clues).
'r' put within 'ease' is 'ERASE'.
(Other definitions for erase that I've seen before include "Do away with" , "Efface" , "Blank out" , "Remove from memory" , "Blot out" .)