Cal. Veh. Code § 40833

Neither the report required by Sections 16000, 16001, 16002, or 16003, the action taken by the department pursuant to Chapter 1 of Division 7 (commencing at Section 16000), the findings, if any, of the department upon which action is based, nor the security filed as provided in that chapter shall be referred to in any way, or be any evidence of the negligence or due care of any party, at the trial of any action at law to recover damages.