One unofficially upholding law leaving it in ruins (9)

I believe the answer is:

vigilante

'one unofficially upholding law' is the definition.

'leaving it in ruins' is the wordplay.
'in ruins' is an anagram indicator.
'leaving'+'it'='leavingit'
'leavingit' anagrammed gives 'VIGILANTE'.

(Other definitions for vigilante that I've seen before include "Self-appointed law enforcer" , "Unofficial policeman" , "Self-appointed lawman" , "Sort of PC not formally recognised" , "Unofficial security figure" .)

I've seen this clue in The Telegraph.

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