Arrested outlaw after turning over couch (6)
I believe the answer is:
nabbed
'arrested' is the definition.
('nab' can be a synonym of 'arrest')
'outlaw after turning over couch' is the wordplay.
'outlaw' becomes 'ban' (banning is a kind of outlawing).
'after turning over' is a reversal indicator.
'couch' becomes 'bed' (I've seen this before).
'ban' back-to-front is 'nab'.
'nab'+'bed'='NABBED'
(Other definitions for nabbed that I've seen before include "Seized suddenly" , "Caught someone doing something wrong" , "Arrested" , "Caught (in the act)" .)