California Code, Financial Code - FIN § 4991

(a) In response to a request by another bank, savings association, credit union, or any other financial institution it is not unlawful for a bank, savings association, credit union, or any other financial institution to provide a written employment reference which advises of the applicants' involvement in a theft, embezzlement, misappropriation, or other defalcation which has been reported to state or federal authorities pursuant to state or federal banking or financial institutions law.  In order for the immunity provided in subdivision (b) to apply, a copy of the written employment reference shall be sent concurrently by the financial institution providing the reference, to the last known address of the person concerning whom the reference is provided.

(b) No bank, savings association, credit union, or any other financial institution shall be civilly liable for providing an employment reference as specified in subdivision (a), unless the information provided is false and the bank, savings association, credit union, or other financial institution providing the false information does so with knowledge and malice.