Ailing vet turned law-enforcer (9)

I believe the answer is:

vigilante

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'law-enforcer' is the definition.
I can't judge whether this defines the answer.

'ailing vet turned' is the wordplay.
'turned' indicates anagramming the letters.
'ailing'+'vet'='ailingvet'
'ailingvet' is an anagram of 'VIGILANTE'.

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(Other definitions for vigilante that I've seen before include "Man on patrol" , "Unofficial security figure" , "Self-appointed lawman" , "Unauthorised law enforcer" , "Self-appointed upholder of the law" .)

I've seen this clue in The Daily Express.

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