Court investigation leader rejected for debate (2,8)

I believe the answer is:

in question

'for debate' is the definition.
(both can mean under discussion)

'court investigation leader rejected' is the wordplay.
'court investigation' becomes 'inquest' (eg a coroner's inquest).
'leader' becomes 'No I' (resembles No 1).
'rejected' says the letters should be written backwards.
'noi' back-to-front is 'ion'.
'inquest'+'ion'='IN QUESTION'

I've seen this clue in The Independent.

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