Not all experts are equal in the eyes of the International Auditing and Assurance Standards Board: On the application of ISA510 and ISA620 by South African registered auditors

Background: The article focuses on inconsistencies in audit approaches when auditors place reliance on the work performed by others. It examines differences in the approach followed by auditors when relying on the work of a predecessor versus the work of an auditor’s expert.

Setting: The study contributes to the limited body of auditing research focusing on the technical application of International Auditing Standards and the functioning of actual audit practice in a South African context. It outlines how auditors apply their professional judgement when using technical auditing standards when comparing the work of a similarly trained expert in the field of accounting and auditing (per ISA510) versus the work of an expert in a field other than accounting and auditing (per ISA620).

Aim: The purpose of this article is to examine and identify inconsistencies in the interpretation and application of ISA510 and ISA620 by a purposefully selected number of registered auditors in South Africa. It considers how inconsistencies in the approach followed when an auditor places reliance on the work of another auditor or an auditor’s expert points to underlying efforts to seek legitimacy and manage legal liability.

Method: Detailed interviews are used to explore auditors’ experiences and challenges with the application of these two ISAs.

Results: Audit quality is not necessarily a function of compliance with professional standards. While ISA510 and ISA620 deal with a situation where an auditor places reliance on the work of a third party, they are interpreted and applied very differently.

Conclusion: The application of ISA510 is part of a rules-based approach to auditing aimed at reducing an auditor’s legal liability rather than enhancing audit quality. The same logic applies to ISA620 except that auditors perceive that their risk exposure is lower because the standard is limited to a single transaction or balance rather than to the entire audit engagement. The application of ISA620 is also useful for convincing internal reviewers, external regulators or audit committees that sufficient appropriate evidence for a complex line item has been obtained. The need to ensure a more robust process for testing complex balances and transactions is not, however, the primary consideration. Regulators and standard setters should not assume that compliance with auditing standards results in better quality audits. At the operational level, the need to manage legal liability and to signal the credibility of test procedures may be more relevant for the execution of audits than ensuring that audit opinions are supported by sufficient appropriate audit evidence. As only two standards, applied in a single jurisdiction, are used to illustrate this point, additional research will be required to determine the extent of inconsistency in the application of auditing standards and how this can result in lower levels of audit quality.