7060.  (a) In addition to any other ground provided by law for
disqualification of a judge, a judge is disqualified from acting in
proceedings under this code concerning the administration of the
decedent's estate, except to order the transfer of a proceeding as
provided in Article 3 (commencing with Section 7070), if any of the
following circumstances exist:
   (1) The judge is interested as a beneficiary or creditor.
   (2) The judge is named as executor or trustee in the will.
   (3) The judge is otherwise interested.
   (b) A judge who participates in any manner in the drafting or
execution of a will, including acting as a witness to the will, is
disqualified from acting in any proceeding prior to and including the
admission of the will to probate or in any proceeding involving its
validity or interpretation.
   (c) The amendments made to former Section 303 by Section 27 of
Chapter 923 of the Statutes of 1987 do not apply in any proceeding
commenced prior to July 1, 1988.