CODE OF CIVIL PROCEDURE § 170.6. Motion to disqualify, Cal Code Civ Proc § 170.6
Summary
(a)
(1) A judge, court commissioner, or referee of a superior court of the State of California shall not try a civil or criminal action or special proceeding of any kind or character nor hear any matter therein that involves a contested issue of law or fact when it is established as provided in this section that the judge or court commissioner is prejudiced against a party or attorney or the interest of a party or attorney appearing in the action or proceeding.
(2) A party to, or an attorney appearing in, an action or proceeding may establish this prejudice by an oral or written motion without prior notice supported by affidavit or declaration under penalty of perjury, or an oral statement under oath, that the judge, court commissioner, or referee before whom the action or proceeding is pending, or to whom it is assigned, is prejudiced against a party or attorney, or the interest of the party or attorney, so that the party or attorney cannot, or believes that he or she cannot, have a fair ...