Make allowances for being swindled by prisoner (7)
I believe the answer is:
condone
'make allowances for' is the definition.
('condone' can be a synonym of 'make allowances for')
'swindled by prisoner' is the wordplay.
'swindled' becomes 'done' (I've seen this before).
'by' is a charade indicator (letters next to each other).
'prisoner' becomes 'con' (abbreviation for 'convict').
'done' after 'con' is 'CONDONE'.
'being' is the link.
(Other definitions for condone that I've seen before include "Overlook - forgive" , "Reluctantly sanction" , "'Excuse, overlook (7)'" , "Nod once (anag) -- make allowances for" , "pardon" .)