憲法第19 條規定：「人民有依法律納稅之義務」。近年來，為求租稅公平，避免人民脫法逃稅，稅捐稽徵機關會針對特殊個案改採「實質課稅」原則，其操作方式依稅捐稽徵法之規定，係由稅捐稽徵機關負舉證責任，並依「實質課稅」原則改定納稅義務人，而非由人民主張。依所得稅法之規定，診所開業醫師之診所所得，與醫院受雇之醫師所得定性並不相同，前者為執行業務所得，後者為薪資所得。但是，當診所開業醫師並非診所實際經營者時，亦即當診所登記負責醫師（出名登記者）與實際經營者（出資借名者）其並非同一人，前者（出名登記者）受雇於後者（出資借名者）成立所謂之「出名登記診所」並負責執行醫療業務時，究竟誰是診所所得之納稅義務人？本文分析三則行政法院判決書內容，凸顯其中不合理之處。

The 19th article of the Constitution states that the people have the obligation to pay taxes according to law. Inrecent years, in order to keep the equity in taxation and avoid tax evasion, the tax authorities would adopt the principle of ”substantive taxation” for the special cases. According to the Tax Collection Act and the principle of ”substantivetaxation,” the tax authorities shall bear the burden of proof in ascertaining the person in charge and responsible for theclinic, but not the people. In accordance with the provisions of the Income Tax Act, the income of the clinic physician isdifferent from that of the physician who works in the hospital; the former is classified into the income from professionalpractice, and the latter is the income from salaries and wages. However, when the clinic physician is not the actualoperator, that is to say, the registered accountable physician (competence-rented employee) is not the actual operator(competence-renting employer), and the latter has employed the former to set up a competence-renting private clinic toimplement medical business, who is the taxpayer? Herein, we analyze three verdicts from Taiwan Administrative Courtand indicate the unreasonable.