Section 491 Of Chapter 5. The Premium From California Insurance Code >> Division 1. >> Part 1. >> Chapter 5.
491
. The rating plan of a motor vehicle liability insurer shall not
provide for an increase in the premium if based upon an accident in
which the insured is not at fault, in any manner, as determined by
either the accident report or the insurer. In the event the insurer
determines that its insured is at fault contrary to an accident
report's specific finding that the insured is not at fault, the
insurer shall reach its conclusion only after an investigation.