What is a person with whom two or more contending parties deposit the subject matter of the controversy; one who mediates between two parties; a mediator; an umpire or referee. Bouvier called?

sequester — (Law) A person with whom two or more contending parties deposit the subject matter of the controversy; one who mediates between two parties; a mediator; an umpire or referee. Bouvier. (Webster's 1913.)

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