fact finder:
(also ‘finder of fact’; plural: ‘fact finders‘ / ‘finders of fact’)

Philip Tamoush, arbitrator, fact finder & mediator, California & Nevada, USA
a person who tries to find or who finds out the truth about something and makes it clear for others;
(in a court of law, also called ‘trier of fact‘ or ‘finder of fact’) the jury or the judge who decides the truth of the facts presented by the lawyers or witnesses;
a particular person, a special master, appointed by the judge to find out the truth of something,

a fact finder (L) questioning locals
In a financial disagreement/dispute between two parties, a fact finder is employed by a party in order to make the other party realise that the first party is showing genuine reasons or facts and come to terms in order to avoid going to the court of law.
When the jury of a criminal case is a fact finder and comes out with its findings, a judge still holds the power of withholding the findings and ask the jury to reconsider their conclusions.
Fact finders are usually experts on matters concerning the legalities of a dispute, who have a good record of conduct and character and who can be impartial while finding facts about issues involved in the dispute.
