California Code, Government Code - GOV § 9904

(a) This chapter may be amended only to further its purposes and only by statute, passed in each house by rollcall vote entered in the journal, two-thirds of the membership concurring and signed by the Governor, if at least 20 days prior to passage in each house the bill in its final form has been printed and made available for public inspection.

(b) This chapter may be amended or repealed by a statute that becomes effective only when approved by the electors.