Legal authority in New York worked on treaty (8)

I believe the answer is:

attorney

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'legal authority in new york' is the definition.
I can't tell whether this definition defines the answer.

'worked on treaty' is the wordplay.
'worked' indicates an anagram.
'on'+'treaty'='ontreaty'
'ontreaty' is an anagram of 'ATTORNEY'.

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(Other definitions for attorney that I've seen before include "One legally acting for another" , "profession" , "Legal professional" , "Legal representative" , "Person legally appointed to act for another" .)

I've seen this clue in The Independent.

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