Blame is possibly tinier when reviewed (14)

I believe the answer is:

responsibility

'blame' is the definition.
(thesaurus)

'possibly tinier when reviewed' is the wordplay.
'when reviewed' is an anagram indicator (letters reviewed or revised).
'possibly'+'tinier'='possiblytinier'
'possiblytinier' is an anagram of 'RESPONSIBILITY'.

'is' acts as a link.

(Another definition for responsibility that I've seen is " Onus".)

I've seen this clue in The Daily Express.

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