Senator organised crime against state (7)
I believe the answer is:
treason
'crime against state' is the definition.
(I've seen this before)
'senator organised' is the wordplay.
'organised' is an anagram indicator.
'senator' with letters rearranged gives 'TREASON'.
(Other definitions for treason that I've seen before include "Senator (anag)" , "Crime of national betrayal" , "Crime of treachery against the state" , "LEse-majestE" , "Deliberate act of betrayal" .)