The provisions of any contract of bailment for the parking or storage of a motor vehicle shall not exempt the bailee from liability, either in whole or in part, for the theft of any motor vehicle, when such motor vehicle is parked or stored with such bailee, and the keys are required by such bailee to be left in the parked or stored vehicle.
Source:
Section 1630.5, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=CIV§ionNum=1630.5..