A case in which the death penalty may be imposed pursuant to this chapter shall be tried in separate phases as follows:
(a) The question of the defendant’s guilt shall be first determined. If the trier of fact finds the defendant guilty of first degree murder, it shall at the same time determine the truth of all special circumstances charged as enumerated in Section 190.2 except for a special circumstance charged pursuant to paragraph (2) of subdivision (a) of Section 190.2 where it is alleged that the defendant had been convicted in a prior proceeding of the offense of murder in the first or second degree.
(b) If the defendant is found guilty of first degree murder and one of the special circumstances is charged pursuant to paragraph (2) of subdivision (a) of Section 190.2 which charges that the defendant had been convicted in a prior proceeding of the offense of murder of the first or second degree, there shall thereupon be further proceedings on the question of the truth of such special circumstance.
(c) If the defendant is found guilty of first degree murder and one or more special circumstances as enumerated in Section 190.2 has been charged and found to be true, his sanity on any plea of not guilty by reason of insanity under Section 1026 shall be determined as provided in Section 190.4. If he is found to be sane, there shall thereupon be further proceedings on the question of the penalty to be imposed. Such proceedings shall be conducted in accordance with the provisions of Section 190.3 and 190.4.
(Repealed and added November 7, 1978, by initiative Proposition 7, Sec. 4.)