Outspoken against old state (5)
I believe the answer is:
vocal
'outspoken' is the definition.
('vocal' can be a synonym of 'outspoken')
'against old state' is the wordplay.
'against' becomes 'v' (abbreviation for 'versus').
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'state' becomes 'cal' (I've seen this in other clues**).
'v'+'o'+'cal'='VOCAL'
(Other definitions for vocal that I've seen before include "not instrumental" , "singing" , "speaking loudly" , "Articulate" , "Relating to the human voice" .)