Kantor

*731 Appellant Baker Marquart LLP represented respondent James R. Kantor on a contingency basis in litigation that resulted in a significant recovery for Kantor. Following the conclusion of Baker Marquart's representation, Kantor filed a demand for fee arbitration in accordance with the parties' contingency fee agreement. In his arbitration demand, Kantor argued Baker Marquart charged him an incorrect contingency fee because Baker Marquart failed to complete two specified tasks. In advance of the arbitration, *732 however, Kantor submitted, and the three-person arbitration panel (panel) accepted, an ex parte "confidential arbitration brief" that Kantor did not provide or otherwise reveal to Baker Marquart. In the confidential brief, Kantor raised and argued additional claims not presented in his arbitration demand. A majority of the panel ruled in Kantor's favor and awarded him a refund of a portion of the fees he had paid to Baker Marquart. In its ruling, the panel majority addressed and relied on claims Kantor raised in the confidential brief.

Baker Marquart filed a motion in superior court to vacate the arbitration award; and Kantor filed a motion to confirm the award. Among…