Attestation Services Example: Emmy Awards, Miss America Pageant, Lottery An attestation service is a type of assurance service in which the CPA firm issues a written communication that expresses a conclusion about the reliability of a written assertion of another party Arens, Loebbecke; Auditing, 8/E o2000 br Prentice Hall. IncArens, Loebbecke; Auditing, 8/E © 2000 by Prentice Hall, Inc. Attestation Services An attestation service is a type of assurance service in which the CPA firm issues a written communication that expresses a conclusion about the reliability of a written assertion of another party. An attestation service is a type of assurance service in which the CPA firm issues a written communication that expresses a conclusion about the reliability of a written assertion of another party. Example: Emmy Awards, Miss America Pageant, Lottery