Different laws govern court annexed arbitration on the one hand and traditional or private arbitration on the other hand.

For traditional / private arbitration, the applicable law depends on whether the court is supervising the conduct of an arbitration vs. the enforcement of an award, whether the arbitration does or does not 'involve' interstate commerce, or international commerce, whether the arbitration was or is conducted in a foreign country, inside, or outside Oregon, and whether the supervising court is federal or state. The differences will not be of much concern to the lawyer or litigant in the arbitration hearing itself, unless the award has any probability of being enforced outside the United States. The differences are beyond the scope of this site.