He's at liberty to be a privileged citizen (7)
I believe the answer is:
freeman
'a privileged citizen' is the definition.
(someone given the freedom of a city)
'he's at liberty' is the wordplay.
I cannot quite see how this works, but
'at liberty' could be 'free' (similar in meaning) and 'free' is present in the answer.
'he' could be 'man' (I've seen this in another clue) and 'man' is present in the answer.
No letters remain.
This explanation may well be incorrect...
'to be' acts as a link.
Can you help me to learn more?
(Other definitions for freeman that I've seen before include "honoured citizen" , "Person at liberty or with special rights" , "One not a slave or serf" , "who never worked slavishly?" , "Old DJ" .)