63 Pa. Stat. § 9.11a
Except by permission of the client engaging him or the heirs, successors or personal representatives of a client, a licensee or a person employed by a licensee shall not be required to, and shall not voluntarily, disclose or divulge information of which he may have become possessed unless the sharing of confidential information is within the peer review process. This provision on confidentiality shall prevent the board from receiving reports relative to and in connection with any professional services as a certified public accountant, public accountant or firm. The information derived from or as the result of such professional services shall be deemed confidential and privileged. Nothing in this section shall be taken or construed as prohibiting the disclosure of information required to be disclosed by the standards of the profession in reporting on the examination of financial statements, or in making disclosures in a court of law or in disciplinary investigations or proceedings when the professional services of the certified public accountant, public accountant or firm are at issue in an action, investigation or proceeding in which the certified public accountant, public accountant or firm is a party.
63 P.S. § 9.11a