California Evidence Code Section 12
(a) This code shall become operative on January 1, 1967, and
shall govern proceedings in actions brought on or after that date
and, except as provided in subdivision (b), further proceedings in
actions pending on that date.
(b) Subject to subdivision (c), a trial commenced before January
1, 1967, shall not be governed by this code. For the purpose of this
(1) A trial is commenced when the first witness is sworn or the
first exhibit is admitted into evidence and is terminated when the
issue upon which such evidence is received is submitted to the trier
of fact. A new trial, or a separate trial of a different issue,
commenced on or after January 1, 1967, shall be governed by this
(2) If an appeal is taken from a ruling made at a trial commenced
before January 1, 1967, the appellate court shall apply the law
applicable at the time of the commencement of the trial.
(c) The provisions of Division 8 (commencing with Section 900)
relating to privileges shall govern any claim of privilege made after
December 31, 1966.