California Code, Civil Code - CIV § 1798.38

If information, including letters of recommendation, compiled for the purpose of determining suitability, eligibility, or qualifications for employment, advancement, renewal of appointment or promotion, status as adoptive parents, or for the receipt of state contracts, or for licensing purposes, was received with the promise or, prior to July 1, 1978, with the understanding that the identity of the source of the information would be held in confidence and the source is not in a supervisory position with respect to the individual to whom the record pertains, the agency shall fully inform the individual of all personal information about that individual without identification of the source.  This may be done by providing a copy of the text of the material with only such deletions as are necessary to protect the identity of the source or by providing a comprehensive summary of the substance of the material.  Whichever method is used, the agency shall insure that full disclosure is made to the subject of any personal information that could reasonably in any way reflect or convey anything detrimental, disparaging, or threatening to an individual's reputation, rights, benefits, privileges, or qualifications, or be used by an agency to make a determination that would affect an individual's rights, benefits, privileges, or qualifications.  In institutions of higher education, “supervisory positions” shall not be deemed to include chairpersons of academic departments.