Oregon Revised Statutes Revenue and Taxation § 305.420

(1) The judge, a magistrate or the clerk of the tax court, on the request of any party to the proceeding, or the attorney of the party, shall issue subpoenas requiring the attendance of and the giving of testimony by witnesses, and subpoenas duces tecum requiring the production of any returns, books, papers, documents, correspondence and other evidence pertaining to the matter under inquiry at any designated place of hearing in the manner prescribed by law in civil actions in courts of this state.

(2) Any employee of the court designated in writing for the purpose by the judge may administer oaths.

(3) Any party to the proceeding may cause the depositions of witnesses residing within or without the state to be taken in the manner prescribed by law for like depositions in civil actions in courts of this state. To that end, the party may compel the attendance of witnesses and the production of returns, books, papers, documents, correspondence and other evidence pertaining to the matter under inquiry.

(4) Subject to ORS 305.390 and 305.392, subpoenas in a proceeding involving the determination of the value of an industrial plant, as defined in ORS 308.408, for purposes of ad valorem property taxation, may be issued as provided in subsection (1) of this section. However, upon petition of the person subpoenaed, the court shall make an order determining if the evidence sought by the subpoena is relevant to the pending proceeding and, if requested by the person subpoenaed, an order as required in the interests of justice to protect the confidentiality of the information subpoenaed.