Person possibly given documentation after prison sentence (4,4)
I believe the answer is:
life form
'person possibly' is the definition.
(person is a kind of life form)
'documentation after prison sentence' is the wordplay.
'documentation' becomes 'form' (I can't justify this - if you can you should give a lot more credence to this answer).
'after' is a charade indicator (letters next to each other).
'prison sentence' becomes 'life' (I've seen this in another clue).
'form' put after 'life' is 'LIFE FORM'.
'given' acts as a link.
Can you help me to learn more?
(Another definition for life form that I've seen is " Being".)