I am right...at the very least..the vehicle has to be CARB eligible to receive a white/green sticker...just doesn't necessarily need to actually have it..the spots are designated to meet new "California Green Building Code"...
http://www.pe.com/articles/vehicles-752853-vehicle-dmv.html
Q. Does a motorist’s vehicle have to display a “clean air vehicle” sticker to be legally parked in one of Riverside’s CAV-designated spaces?
A. Clarifying information included in a Sept. 29 traffic column , those “clean air vehicle” spaces sprinkled around Riverside are not restricted only to a zero or near-zero emission vehicle displaying a Department of Motor Vehicles-issued clean-air vehicle decal.
Rather, any qualified hybrid or clean-air vehicle (based on a list established by the California Air Resources Board), may use such a parking space, regardless of whether it displays a CAV decal.
“Some vehicles which are eligible for a (CAV) sticker may not have one, be it because of owner choice or because DMV limits the availability,” Riverside Regulatory Compliance Manager Kevin Street wrote in an email. “The city will allow eligible vehicles to use the spaces, whether or not they have a sticker and regardless of color of the sticker.”
The city’s CAV spaces, Street noted, were established in line with the California Green Building Code and intended to be reserved for zero and near-zero emission vehicles such as those powered entirely by batteries (Chevrolet Spark EV, Nissan Leaf and others) and plug-in hybrids (Chevrolet Volt, Toyota Prius Plug-in and others).
Also included, according to Street, are neighborhood electric vehicles, compressed natural gas vehicles (if the equipment was installed by the vehicle manufacturer), high-efficiency vehicles regulated by the federal Environmental Protection Agency and those displaying DMV-issued carpool lane stickers.
“In enforcing the use of these spaces,” Street said, “the city looks for either the presence of any DMV-issued CAV decal. Or, if there’s no sticker, whether the vehicle was eligible to receive one.”