Cal. Code Regs. tit. 25 § 6164
Upon agreement between the claimant and the public entity, a mutually acceptable third party or parties may review the claim and make advisory recommendations thereon to the head of the public entity for its final determination. In reviewing the claim and making recommendations to the public entity, the third party or parties shall be guided by the provisions of this Article.
Except to the extent the confidentiality of material is protected by law or its disclosure is prohibited by law, a public entity shall permit the claimant to inspect all files and records bearing upon his claim or the prosecution of the claimant's grievance. If a claimant is improperly denied access to any relevant material bearing on the claim, such material may not be relied upon in reviewing the initial determination.
Cal. Code Regs. Tit. 25, § 6164