California Code, Revenue and Taxation Code - RTC § 11162

(a) The ordinance proposing the assessment complies with both of the following:

(b) The ordinance proposing the assessment is approved by two-thirds of all members of the board of supervisors.

(c) The ordinance proposing the assessment is submitted to the electorate of the city and county and is approved by a majority vote of the voters voting on the ordinance.

(d) The board of supervisors transmits to the department and the Franchise Tax Board a certified copy of the ordinance imposing that assessment immediately after the results of the election described in subdivision (c) are certified.

(e) The ordinance proposing the assessment does not create different classes of vehicles (whether by type, size, passenger capacity, value or cost, fuel consumption, or any other characteristic) for differential taxation (whether by rate, method, assessment ratio, or any other means), except that the exemptions from the vehicle license fee set forth in Part 5 (commencing with Section 10701) shall be applicable.