At fault, not entirely sober, Pilsner drunk (11)
I believe the answer is:
responsible
'at fault' is the definition.
(thesaurus)
'not entirely sober pilsner drunk' is the wordplay.
'not entirely' means to remove the last letter (not all of the word).
'drunk' indicates an anagram.
'sober'+'pilsner'='soberpilsner'
'soberpilsner' with its last letter removed is 'soberpilsne'.
'soberpilsne' with letters rearranged gives 'RESPONSIBLE'.
(Other definitions for responsible that I've seen before include "Answerable; trustworthy" , "Having obligations" , "Answerable (for something)" , "Morally accountable for one's behaviour" , "To blame" .)