It's again demonstrable to be worthy of censure (10)

I believe the answer is:

reprovable

'worthy of censure' is the definition.

'it's again demonstrable' is the wordplay.
'it's again' becomes 're' (prefix meaning 'again').
'demonstrable' becomes 'provable' (synonyms).
're'+'provable'='REPROVABLE'

'to be' acts as a link.

I've seen this clue in The Guardian.

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