Judge associated with the top people: I'm surprised he's been driven out (7)
I believe the answer is:
refugee
'he's been driven out' is the definition.
'judge associated with the top people i'm surprised' is the wordplay.
'judge' becomes 'ref'.
'associated with the top people' becomes 'u' (as in U and non-U language).
'i'm surprised' becomes 'gee' (exclamation of surprise).
'ref'+'u'+'gee'='REFUGEE'
(Other definitions for refugee that I've seen before include "War-forced migrant" , "Person who seeks sanctuary in another country" , "Asylum seeker" , "Displaced exile" , "One fleeing homeland" .)