비감사서비스의 제공과 감사투입시간

In recent years, there has been a heated debate over whether auditors should be allowed to any non-audit services (“NAS”) to their audit clients. The regulatory and other proponents of auditor-provided NAS argue that performing both audit and non-audit services for the same client increases audit effectiveness and audit efficiency because it promotes a more comprehensive understanding of the client. However, opponents of auditor-provided NAS, many of whom advocate a complete ban on such services, argue that acting in a dual capacity as auditor and consultant/adviser compromises auditor independence and objectivity. This paper investigates whether the provision of NAS affects auditor's hours spent on audit service. Prior studies suggest that auditor independence is compromised when the client pays high non-audit fees to the same auditor. These studies directed at the extent of audit-client economic bonds and any resulting threat to auditor independence have concentrated on the provision of NAS to audit clients (Frankel et al. 2002). However, a number of studies show Frankel et al.'s results are sensitive to the method used to estimate discretionary accruals, the specific research design, and the sample selection process (Ashbaugh et al. 2003; Chung and Kallapur 2003; Larcker and Richardson 2004 etc). These papers all fail to consistent evidence that NAS is associated with lower audit or accounting quality. Also, previous research indicates that the provision of NAS improves audit effectiveness since auditors are able to transfer knowledge from a non-audit service to an audit task(Simunic 1984; Palmrose 1986; O'Keefe et al. 1994). The premises of the previous studies imply that the provision of NAS would decrease the audit hours because auditors would not devote efforts and time fully when their independence is impaired and because auditors can save audit hours when the provision of NAS has knowledge spillover effect on audit services. The results of this study, on the contrary to the expectation, show that the provision of NAS increases audit time spent on audit services. The positive relation between audit hours and NAS fees is more manifested when the auditors are Big 4 auditors, the NAS is not related to tax services, and prior to 2003 when the provision of NAS is restricted. The findings imply that the provision of NAS does not impair auditor's independence and also does not save audit time. Auditors would devote more efforts and hours on the audit service for the clients who pay high fees because the client are more important for them. When tests are confined to observations where audit hours are positive, we find evidence of a positive associated between audit hours and the provision of NAS. A variety of sensitivity analyses does not change our basic conclusion. This study contributes to the literature in several ways. First, although there are many studies that examine the provision of NAS by the auditor (Simunic 1984; Palmrose 1986; O'Keefe et al. 1994; Frankel et al. 2002; Ashbaugh et al. 2003; Antle et al. 2006; Hwang et al. 2005; Coulton et al. 2007 etc), these studies have all focused on whether auditor' independence is compromised by the economic bond created from the provision of NAS. In extended prior evidences on the extent to which auditor-client economic bonding (and especially the provision of NAS) is associated with evidence of higher quality auditing, we recognize varied the conclusions of research appear to be. Second, this study extends the literature on the transfer of knowledge between the audit hours and knowledge transfer in auditing. In the studies literature, some prior studies use archival data to obtain evidence on knowledge spillovers. This research has policy implication. The regulatory body has restricted the provision of NAS since 2003 to improve the auditors' independence and audit quality. However, if the auditor's time and efforts are increased when the NAS is provided, the effects of the restriction on audit quality should be carefully reexamined. Therefore, the results of this paper may provide useful information to academic researchers and regulatory bodies that evaluate the reliability of external audit by using non-audit fees and audit hours information. In this respect, this study has important policy implications.