Perfect half of family raised in criminal society (5)
I believe the answer is:
mafia
'criminal society' is the definition.
(I've seen this before)
'perfect half of family raised' is the wordplay.
'perfect' becomes 'ai' (I've seen this in other clues).
'half of' suggests halving the letters.
'raised' shows that the letters should be reversed in order.
'family' with half the letters taken is 'fam'.
'ai'+'fam'='aifam'
'aifam' in reverse letter order is 'MAFIA'.
'in' acts as a link.
(Other definitions for mafia that I've seen before include "Our family" , "Italian criminal organisation" , "Sicilian criminal organisation" , "Sicilian one" , "connection claimed to 23 [JFK]" .)