Damned ringleader framed by one on trial (8)
I believe the answer is:
accursed
'damned' is the definition.
(I've seen this before)
'ringleader framed by one on trial' is the wordplay.
'ringleader' becomes 'r' (first letter of ring).
'framed by' means one lot of letters goes inside another.
'one on trial' becomes 'accused' (I've seen this in another clue).
'r' put inside 'accused' is 'ACCURSED'.
(Other definitions for accursed that I've seen before include "Goddamn" , "Cue cards (anag) - doomed" , "Wretched" , "Hateful" , "Detestable (colloq.)" .)