Cal. Insurance Code § 791.12

No insurance institution or agent may base an adverse underwriting decision in whole or in part on the following: (a) On the fact of a previous adverse underwriting decision or on the fact that an individual previously obtained insurance coverage through a residual market mechanism; provided, however, an insurance institution or agent may base an adverse underwriting decision on further information obtained from an insurance institution or agent responsible for a previous adverse underwriting decision. The further information, when requested, shall create a conclusive presumption that the information is necessary to perform the requesting insurer’s function in connection with an insurance transaction involving the individual and, when reasonably available, shall be furnished the requesting insurer and the individual, if applicable. (b) On personal information received from an insurance-support organization whose primary source of information is insurance institutions; provided, however, an insurance institution or agent may base an adverse underwriting decision on further personal information obtained as the result of information received from an insurance-support organization. (c) On the fact that an individual has previously inquired and received information about the scope or nature of coverage under a residential fire or property insurance policy, if the information is received from an insurance-support organization whose primary source of information is insurance institutions and the inquiry did not result in the filing of a claim. (d) On the fact that an accident involving a peace officer, member of the Department of the California Highway Patrol, or firefighter has been reported and the insurer retains no liability pursuant to Section 488.5 and subdivision (b) of Section 557.5.