California Code, Labor Code - LAB § 5953

The findings and conclusions of the appeals board on questions of fact are conclusive and final and are not subject to review. Such questions of fact shall include ultimate facts and the findings and conclusions of the appeals board. The appeals board and each party to the action or proceeding before the appeals board shall have the right to appear in the review proceeding. Upon the hearing, the court shall enter judgment either affirming or annulling the order, decision, or award, or the court may remand the case for further proceedings before the appeals board.