세무보고 공격성이 감사인이 인지한 기대감사시간, 실제 감사보수 및 감사시간에 미치는 영향 = The Effect of Tax Reporting Aggressiveness on the Auditors` Perceived Expected Audit Hours, Actual Audit Fees and Audit Hours

다국어 초록 (Multilingual Abstract)

This study investigates the effect of tax reporting aggressiveness on auditors` expected audit hours, actual audit hours, and audit fees. Earlier studies view corporate tax aggressiveness as increasing firm value since aggressive tax strategy saves tax payments and cash outflows. In contrast, recent papers focus on agency problem arising from tax aggressive activities. For example, aggressive tax positions can decrease firm value by increasing potential nontax costs. Managers need to invest resources to plan for tax strategy and to pay significant fees for accounting and legal services. Such costs can be significantly large in cases where aggressive tax positions are challenged by tax authorities (Slemrod 2004; Desai and Dharmapala 2006). Further, managers may engage in tax aggressive activities for opportunistic purposes rather than for maximizing firm value. In such cases, aggressive tax positions are likely to increase information risk as well because opportunistic managers have incentive to engage in complex transactions and opaque reporting to obscure their opportunism and to reduce risk of being caught by regulators. In line with this, recent studies argue that corporate tax aggressiveness decreases quality of financial reporting and disclosures and thus increases information risk (Balakrishnan et al. 2012; Park 2012; Kang and Ko. 2014). Relatedly, corporate tax aggressiveness is likely to increase audit risk since auditor`s role is to decrease information risk by improving credibility of firm`s financial reporting and disclosures. Therefore we expect that auditors increase audit hours and audit fees for tax aggressive firms to control for their audit risk. Prior research documents that tax reporting aggressiveness measured as effective tax rate increases audit fees (Donohoe and Knechel 2014; Shim 2009). They argue that tax aggressive firms pay fee premium for external audit services because firm`s aggressive tax avoidance strategy increases audit risk and complexity. However, these studies do not examine whether the audit fee premium for tax aggressiveness is conditional on increases in audit efforts. We extend this line of research by examining whether firm`s aggressive tax reporting influences not only audit fees but also auditor`s expected audit hours and audit efforts measured as audit hours. We construct proxy for tax aggressiveness using GAAP ETR　and CASH ETR introduced by Dyreng et al. (2008) and CFO (cash flow from operations) ETR introduced by Guenther et al. (2014). Following Donohoe and Knechel (2014), we classify firms as tax aggressive if they are in the lowest quintile of GAAP ETR, CASH ETR, or CFO ETR by year within the same industry. Our sample covers KOSPI and KOSDAQ listed firms in non-financial industries with fiscal year-end in December from 2008 to 2013. We document several findings. First, we find that auditor`s expected audit hours significantly increase for tax aggressive firms. The result suggests that auditors perceive corporate tax avoidance activities as increasing audit risk. Second, we do not find the positive association between tax aggressiveness and audit fees as documented by Donohoe and Knechel (2014)　and Shim (2009). Whereas tax aggressiveness has no incremental effect on audit fees for our sample firms in general, audit risk for tax aggressive firms is compensated with additional audit fees only for Big 4 auditors. Third, we find that auditors increase audit hours for tax aggressive clients, suggesting that tax aggressiveness positively influence audit efforts. Lastly, when we partition the sample into pre- and post-IFRS adoption period, we find that the positive relation between tax aggressiveness and audit hours is stronger during pre-IFRS adoption period and for Big 4 auditors. Overall, our results suggest that corporate tax aggressiveness influences the level of audit efforts exerted by auditors measured as both expected and actual audit hours. However, auditors are not rewarded with audit fee premium for exerting incremental efforts for tax aggressive firms because of competitive nature of Korean audit market. Incremental audit efforts for tax aggressive firms are compensated only for Big 4 auditors. Our study makes several contributions. First, this study is the first to document the effect of corporate tax aggressiveness on audit efforts measured as expected and actual audit hours. Second, we contribute to the audit fee literature by showing that increased audit efforts for tax aggressiveness are not compensated for Korean auditors in general in contrast to prior finding of the positive relation between tax aggressiveness and audit fees (Donohoe and Knechel 2014; Shim 2009). Our results manifest distinct nature of Korean audit market and thus provide implications to academicians, practitioners, and regulators.