California Code, Insurance Code - INS § 11732.5

Rates shall not be unfairly discriminatory.  Rates are unfairly discriminatory if, after allowing for practical limitations, price differentials fail to reflect equitably the difference in expected losses and expenses.  A rate of an insurer shall not be deemed unfairly discriminatory because different premiums result for policyholders with like loss exposures but different expenses, or like expenses but different loss exposures, as long as the rate reflects the differences with reasonable accuracy.