본 연구는 감사인 교체여부와 감사인 교체사유, 감사인 비교체 사유 등이 감사품질에 다른 영향을 미치는지 분석하였다. 연구대상은 2002년부터 2004년까지 금융감독원의 전자공시스템에서 감사인 선임관련 자료를 입수할 수 있는 표본이며, 감사품질은 총발생액, 수정 Jones 모형과 현금흐름을 반영하여 추정한 재량적 발생액을 대용변수로 활용하였다. 분석 결과는 다음과 같다. 첫째, 감사인 교체여부와 감사품질의 유의적인 설명관계를 발견하지 못하였다. 둘째, 감사인이 규제당국의 지정에 의하여 교체되었을 경우에 재량적 발생액이 매우 유의적으로 낮아지는 것을 알 수 있었다. 셋째, 감사인 비교체 사유를 감사인 유지와 재계약의 경우로 분리하여 검증한 결과, 감사인 재계약 변수가 재량적 발생액에 양(+)의 설명력을 보였으나 통계적으로 유의하지는 않았다. 이러한 결과는 당국의 강행성으로 감사인이 지정선임되거나 감사인 유지규정이 준수될 때 감사인의 독립성이 확보되는 것을 시사한다. 본 연구는 감사인 교체여부뿐만 아니라 어떠한 교체사유 혹은 비교체 사유가 감사품질을 개선시킬 수 있는지 세부적으로 검증하였다는 점에서 의의가 있을 것이다. 특히 본 연구는 관련당국이 감사인 선임 규정을 보완하고자 할 때 실무적 단서로 활용할 수 있다는 점에서 공헌성을 인정받을 것이다.
Recent events have provide evidence of an association between audit quality and auditor changing. These issues have focused the public's eye on the work of external auditors. For example, certain parties have called for mandatory audit firm rotation. Some of results have supported that a new auditor by the policy of mandatory audit rotation would bring to bear greater skepticism and accounting transparency, implying that long-standing auditor-client relationships potentially may impair the auditors' independence. Conversely, some of opponents argue that mandatory firm rotation would curtail audit quality because the auditor would lack familiarity with the client and its industry. This study examines whether mandatory auditing rules increase audit quality. In Korea, regulatory authority(e.g FSS, financial supervisory service) exercises mandatory auditor change, designation and retention. Although there has been considerable interest in mandatory auditor rotation as a means to protect auditor independence, prior research seldom showed audit quality with respect to 'the types of auditor changes'. For example, because auditor changes may be result from the designation of regulatory authority or voluntary of firms, we need to examine the effect of mandatory or voluntary auditor changing respectively. In the same context, auditor non-changes can be generated from auditor retention or renewable contract. Under these circumstances, we infer that audit qualities may be different from each other. In particular, because auditor designation and retention are mandated by regulatory authority, auditors are not vulnerable from firms. On the other hand, firms may change or renew auditors voluntarily in the end of mandatory retention(after 3 years). Because situations are up to firms, auditors' independences can be vulnerable and decrease audit quality. Obviously, we ascertain the differences of audit qualities between audit change, designation and retention, respectively. We hypothesize that 1) auditor change increases audit quality, 2) in the only auditor change group, audit quality of designation by regulatory authority is higher than that of firms' voluntary and 3) in the only auditor non-change group, audit quality of retention by regulatory authority is higher than that of firms' renewable contract. We define audit quality as the estimation of total accruals and discretionary accruals with modified Jones model and cash flow. High audit quality is more likely to detect accounting irregularities, object to the use of questionable accounting practices, and limit discretion over accrual choices for client firms. The test samples consist of 1,667(for full samples), 303(only for audit changes) and 1,364(no audit changes) selected from the Korea Stock Exchange(KSE) listed companies during the year 2002~2004. Consistent with our hypothesis, we find that the level of discretionary accruals is significantly lower for firms with designated auditors than firms that freely select their auditors. We also find that the level of discretionary accruals of audit renew has partly significant higher than auditor retention. Because these compound effects related to auditor changes, we are not sure that only auditor change can improve audit quality. Overall, our results are consistent with the notion that mandatory audit policies can enhance audit quality and the credibility of financial reporting. This paper contributes to studying a forced auditor change setting (versus a voluntary auditor change setting). Futhermore, this paper allows for a more direct examination of how audit quality is affected by a mandatory auditor change and an increase in auditor independence.