California Code, Public Resources Code - PRC § 25722

(a) On or before January 31, 2003, the commission, the Department of General Services, and the State Air Resources Board, in consultation with any other state agency that the commission, the department, and the state board deem necessary, shall develop and adopt fuel-efficiency specifications governing the purchase by the state of motor vehicles and replacement tires that, on an annual basis, will reduce petroleum consumption of the state vehicle fleet to the maximum extent practicable and cost-effective.

(b) In developing the specifications, the commission and the department shall jointly conduct a study to examine state vehicle purchasing patterns, including the purchase of after market tires, and to analyze the costs and benefits of reducing the energy consumption of the state vehicle fleet by no less than 10 percent on or before January 1, 2005.

(c) The study shall include an analysis of all of the following topics:

(d) On or before January 31, 2003, and annually thereafter, the commission, the Department of General Services, and the State Air Resources Board, in consultation with any other state agency that the commission, the department, and the state board deem necessary, shall develop and adopt air pollution emission specifications governing the purchase by the state of passenger cars and light-duty trucks that meet or exceed California's Ultra-Low Emission Vehicle (ULEV) standards for exhaust emissions (13 Cal. Code Regs. 1960.1).

(e) If the study described in subdivision (b) determines that lower cost measures exist that deliver petroleum reductions equivalent to applicable federal requirements governing the state purchase of passenger cars and light-duty trucks, the state shall pursue a waiver from those federal requirements.