Oregon Revised Statutes Justice Courts § 55.090

(1) Except as may otherwise be provided by ORS 55.040, no attorney at law nor any person other than the plaintiff and defendant shall become involved in or in any manner interfere with the prosecution or defense of the litigation in the department without the consent of the justice of the justice court, nor shall it be necessary to summon witnesses. But the plaintiff and defendant may offer evidence in their behalf by witnesses appearing at the hearing, and the justice may informally consult witnesses or otherwise investigate the controversy and give judgment or make such orders as the justice deems right, just and equitable for the disposition of the controversy.

(2) Notwithstanding ORS 9.320, a party that is not a natural person, state or any city, county, district or other political subdivision or public corporation in this state may appear as a party to any action in the department without appearance by attorney.