Engineer boycotted site — it must be settled by criminal (4,2,7)

I believe the answer is:

debt to society

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'settled by criminal' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'engineer boycotted site' is the wordplay.
'engineer' is an anagram indicator.
'boycotted'+'site'='boycottedsite'
'boycottedsite' is an anagram of 'DEBT TO SOCIETY'.

'it must be' is the link.

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I've seen this clue in The Guardian.

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