Comment 6 to Section 2.3 of the Model Rules of Professional Conduct provides that, "When a question concerning the legal situation of a client arises at the instance of the client's financial auditor and the question is referred to the lawyer, the lawyer's response may be made in accordance with procedures recognized in the legal profession. Such a procedure is set forth in the American Bar Association Statement of Policy Regarding Lawyers' Responses to Auditors' Requests for Information, adopted in 1975."
The Statement of Policy is published in the Business Lawyer (v.31, p.1709, 1975) and the Auditor's Letter Handbook (compiled by the ABA Section of Business Law Committee on Audit Inquiry Responses).