ABA ethics opinions provide guidance as to the ABA Model Rules of Professional Conduct. Those rules are not applicable in California. However, in the absence of a California professional rule or other applicable California authority, courts may look to the ABA Model Rules and ethics opinions for guidance, where those rules do not conflict with California policy. City and County of San Francisco v. Cobra Solutions, Inc., 38 Cal. 4th 839, 852 (2006).