本研究主要探討我國設置審計委員會的企業是否較延續採用監察人制度的企業更能抑制企業租稅規避。美國於2002年在沙賓法案中推行審計委員會制度,我國亦於2006年在證券交易法中增設公開發行公司設置審計委員會相關規定。Lisic(2014)指出設置審計委員會企業會降低其利用所得稅費用認列之盈餘管理行為;許文馨(2014)探討設置審計委員會的企業會有較低的盈餘管理程度。本研究探討設置審計委員會公司是否較能抑制其租稅規避,預期設置審計委員會的企業,相較於採用監察人的企業更能監督並抑制企業從事租稅規避。 本研究使用2007年至2013年我國上市櫃企業,運用Hanlon and Heitzman(2010)中總財稅差異與有效稅率與Frank(2009)採用的永久性財稅差異作為本研究之避稅指標。本研究分為兩部分,第一部分為全體上市櫃樣本分析,檢視設置審計委員會樣本與其他樣本避稅程度情形;第二部分以設置審計委員會樣本作為實驗組,使用傾向分數配對法(Propensity Score Matching)配對未設置審計委員會的公司為控制組進行實證分析。 第一部分的實證結果發現設置審計委員會的企業,相對有較低的永久性財稅差異;第二部分的實證結果顯示設置審計委員會的企業,總財稅差異與永久性財稅差異較採用監察人制度的企業為低。兩部份均表示設置審計委員會之企業有較低的避稅行為。另外,兩部分皆未發現審計委員會之設置與有效稅率之顯著差異。
The United States has implemented the audit committee since the Sarbanes-Oxley Act of 2002, and Taiwan (R.O.C.) followed up by enacting provisions regulating audit committee’s set-up in public companies in 2006, expecting to enhance the effectiveness of corporate governance. According to Lisic (2014) and Hsu, Wen-Hsin (2010), enterprises adopting audit committee reduce their earnings management. This paper aims to discuss whether audit committee will be more effective in inhibiting enterprises’ tax avoidance activities than supervisor scheme. The research takes domestic listed firms as samples during the period of 2007 and 2013, utilizing book-tax difference, GAAP effective tax rate (Hanlon and Heitsman 2010) and permanent book-tax difference (Frank 2009) as three indexes of tax avoidance activities. The study is divided into two parts: the first one is full-data analysis, and the second one uses Propensity Score Matching (PSM) to select matched samples for further analysis. The empirical results of both parts suggest that those enterprises setting up audit committee have less tax avoidance behavior, and therefore, audit committee is proven to be more effective to deter enterprises from tax avoidance than the supervisor scheme.