Oregon Revised Statutes Revenue and Taxation § 305.215

(1) Where there are conflicting claims to a personal exemption credit for a dependent allowed under the personal income tax laws, the Department of Revenue shall notify by certified mail each person claiming the same dependent, and shall set a time and place convenient to each claim insofar as it is practicable, for a joint determination of the conflicting claims. Each person so notified who appears shall bring the information from the person's income tax returns or reports that supports the person's claim, together with all records, data or other evidence providing the necessary supporting material to the information shown on the income tax return. All such material shall be available for inspection by the other claimant, notwithstanding any provision of ORS 314.835, 314.840 or 314.991. If either claimant fails or refuses to appear or bring such information in part or in whole, the department shall make its determination on the basis of all the information and evidence supplied. The provisions of this chapter relating to the administration of the personal income tax laws apply to the determination.

(2) If an appeal is taken to the Oregon Tax Court pursuant to ORS 305.560 by either claimant, each claimant shall make available to the court information from the person's income tax returns or reports supporting that person's claim, together with all evidence or supporting data furnished to or subpoenaed by the Department of Revenue, as well as such other information as may be presented to the court in the manner otherwise provided for in the hearing of cases in the Oregon Tax Court. If either claimant fails or refuses to appear or bring such information in part or in whole, the court shall make its determination on the basis of all the evidence introduced. All such evidence shall constitute a public record and shall be available to the parties and the court notwithstanding any provision of ORS 314.835, 314.840 or 314.991.