獨立董事在企業租稅規劃的監督效果

The Supervision Effect of an Independent Director on Corporate Tax Planning

本研究旨在探討企業設置獨立董事對企業租稅規劃的監督效果。本研究以我國2008 年至2014 年上市櫃企業為研究對象，以當期所得稅費用有效稅率、所得稅費用有效稅率與財稅差異等三種租稅規劃代理變數與企業是否設立獨立董事之相關性，來評估設置獨立董事是否對租稅規劃具有監督效果。研究成果顯示，有設立獨立董事的企業相較於未設置獨立董事的企業，其當期所得稅費用之有效稅率、所得稅費用有效稅率為較高，財稅差異較小，顯示設置獨立董事確實有監督企業租稅規劃的作用。其次，本研究以有設置獨立董事之企業為樣本對象，並探討上述三種租稅規劃代理變數與企業設立會計專家獨立董事之相關性，結果發現設置會計專家獨立董事相較於其他專業獨立董事企業之租稅規劃較低。最後，席次控制比率較高或者屬家族企業時，會使獨立董事與租稅規劃之相關性降低，不利於獨立董事對租稅規劃之監督。

This study investigated the supervision effects of independent directors on corporate tax planning during 2008-2014 in Taiwan. Three tax planning proxy variables such as current effective tax rate, income tax expense effective tax rate, or book-tax difference, have been used to investigate if the supervisory effect of independent director influences tax planning behavior. Consistent with the supervision function, this study found that in firms employed more independent directors the likelihood of engaging in tax planning was lower. This study also found that independent directors with expertise in accounting had a better supervisory effect compared to other independent directors. Finally, in firms with a higher ratio of control interest directors on the board or in family firms the relationship between independent directors and tax planning was inversely affected, as supervision by independent directors of tax planning is seldom conducted in these types of firms.