California Code, Revenue and Taxation Code - RTC § 7286.40

(a) The Legislature finds and declares that the transactions and use tax proposed to, and approved by, the voters of the County of Los Angeles on the March 7, 2017, ballot as Measure H was valid and authorized under Section 7285.5 and conforms to Part 1.6 (commencing with Section 7251), and continues to be valid and authorized. This subdivision is declarative of, and clarifies, existing law.

(b) Pursuant to subdivision (a), the board shall enter into a contract with the County of Los Angeles to perform all functions incident to the administration and operation of the transactions and use tax ordinance described in subdivision (a) and shall collect the tax in all districts within the county where the aggregate tax is 0.25 percent or more below the limitation specified in Section 7251.1. The contract with the county shall comply with Section 7270, and shall ensure the collection of the tax commences on October 1, 2017.