Scoundrel, British, to go without protection (10)
I believe the answer is:
blackguard
'scoundrel' is the definition.
(blackguard is a kind of scoundrel)
'british to go without protection' is the wordplay.
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'to go without' becomes 'lack'.
'protection' becomes 'guard' (I've seen this before).
'b'+'lack'+'guard'='BLACKGUARD'
(Other definitions for blackguard that I've seen before include "Cad" , "Villain" , "miscreant" , "rogue" , "Contemptible scoundrel" .)