Minn. Stat. § 571.83: JOINDER AND INTERVENTION BY PERSONS IN INTEREST.

If it appears that a person, who is not a party to the action, has or claims an interest in any of the disposable earnings, other indebtedness, money, or other property, the court shall permit that person to intervene or join in the garnishment proceeding. If that person does not appear, the court may summon that person to appear or order the claim barred. The person so appearing or summoned shall be joined as a party and be bound by the judgment.