Exonerate (7)
I believe the answer is:
absolve
'exonerate' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for absolve that I've seen before include "Acquit - free of blame" , "Set free from guilt" , "Forgive sins" , "Exculpate" , "Declare (someone) free of guilt" .)