adjudicator
US /əˈdʒuː.də.keɪ.t̬ɚ/
UK /əˈdʒuː.də.keɪ.t̬ɚ/

1.
a person who makes an official decision about who is right in a dispute
:
•
The independent adjudicator ruled in favor of the claimant.
•
She was appointed as the adjudicator for the poetry competition.