Cal. Const. art. XIX, § 7

If the Legislature reduces or repeals the taxes described in Section 2 and adopts an alternative source of revenue to replace the moneys derived from those taxes, the replacement revenue shall be deposited into the Highway Users Tax Account, dedicated to the purposes listed in Section 2, and allocated to cities, counties, and areas of the State pursuant to Section 4. All other provisions of this article shall apply to any revenues adopted by the Legislature to replace the moneys derived from the taxes described in Section 2.