A lawyer set free any otter (8)
I believe the answer is:
attorney
'a lawyer' is the definition.
(I know that lawyer can be written as attorney)
'set free any otter' is the wordplay.
'set free' indicates anagramming the letters (the letters are free to move around).
'any'+'otter'='anyotter'
'anyotter' is an anagram of 'ATTORNEY'.
(Other definitions for attorney that I've seen before include "brief" , "Person legally appointed to act for another" , "Legal professional" , "Lawman" , "profession" .)