本研究以2014 年至2019年之臺灣上市、上櫃公司資料,進行迴歸分析,探討會計師事務所任期、獨立董事專業背景多樣性與租稅規避之關聯性。參考過去研究的作法,本文以六年期現金有效稅率衡量企業租稅規避程度。實證結果顯示,在其他條件不變之下,會計師事務所任期愈長,有效稅率越低,推測原因可能係長期委任關係下,經濟依存度也較高,同時會計師事務所也越深入了解受查客戶產業特性,並提供全方位的稅務輔導及規劃,使得有效稅率下降。而獨立董事背景多樣化,則與有效稅率呈顯著正相關,意即獨立董事專業背景愈豐富多元,監督能力越高,包括愈能夠有效的約束降低管理者從事極積的避稅行為作用。
Using Taiwan listed firms from 2014 to 2019 as a sample, this study investigates the relationship among the audit tenure, the diversity of independent directors' professional backgrounds and firms’ tax avoidance. Following prior research, the tax avoidance is measured by firms’ average six-year cash effective tax rate. The empirical results show that firms’ effective tax rate is negatively associated with audit tenure. This result suggests that there is more economic dependence when audit tenure gets longer, and auditors can provide more tax service to lower the effective tax rate when auditors possesse better industry-specific knowledge. Further, the empirical evidence shows that there is a significantly positive relationship between the diversity of independent directors’ expertise and firms’ effective tax rate, suggesting that the diversity of independent directors’ expertise can provide better monitoring functions to effectively lower firms’ tax avoidance behavior.