Senator arranged a serious crime (7)

I believe the answer is:

treason

'a serious crime' is the definition.
(treason is a crime)

'senator arranged' is the wordplay.
'arranged' indicates anagramming the letters (letters rearranged).
'senator' is an anagram of 'TREASON'.

(Other definitions for treason that I've seen before include "Serious crime" , "Betrayal of one's nation" , "Senator (anag)" , "Disloyalty (to one's country)" , "Lese-majesty" .)

I've seen this clue in The Guardian.

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