일본 세법상의 신의칙에 관한 이론적 고찰-학설과 판례를 중심으로

Article 1(2) of the Japanese Civil Code states that “the exercise of rights and performance of duties must be done in good faith.” This is referred to as the principle of good faith, or a provision on good faith. The principle applies in a case where: (a) a person presents an argument that goes against his past words and deeds, thereby resulting in the infringement of a third party’s interests; and (b) such argument is invalidated. Whether the principle of good faith is applicable to tax laws is still being debated. While the Korean law has directly incorporated the good faith principle in its tax law through codification, Japan has not done so yet. In light of the difference between the two, the Korean law is mostly focused on the scope of the application of the good faith principle, whereas the Japanese law concerns the application of the principle itself, and this is the reason for persistence of the argument that there is no room for the application of the good faith principle in tax laws based on the principle of no taxation without law. Whether the good faith principle applies to a relationship between the tax authority and taxpayers has much relevance for the modern day tax administration. A question might arise: if the tax authority’s past practices violate the relevant statutes, and later the argument that runs counter to such practices (e.g., taxation disposition) turns out to be legitimate, does the good faith principle apply in such instance? If the good faith principle does not apply, the tax authority may opt for a legitimate argument initially made or decide to impose tax. The principle of no taxation without law intends to ensure: (a) predictability and legal stability in the relationship between taxpayers and tax administrations; and (b) that the tax authority does not impose a duty to pay tax on taxpayers for what is not primarily designated as the legal elements. Also, under the principle, the tax authority may not unilaterally decide not to collect tax or exempt a certain taxpayer from his tax liability, in an effort to uphold the equity of taxation and fairness in tax burden sharing. In that regard, the principle of no taxation without law, and particularly the requirements for application of the good faith principle and its scope of application, may subject to restriction with regard to the principle of the equity of taxation. The application of the principle of good faith in the study of tax law has been a topic of controversy, because the good faith principle itself (a) clearly violates the principle of no taxation without law or the rule of law structurally; and (b) serves as a critical means of change. Yet, the judicial cases and theories have so far affirmed the possibility of its application, seemingly because, as the Tokyo Regional Court stated in its judgment, the practical function of the good faith principle or societal demands of protecting taxpayer confidence have reached a level where they cannot be disregarded any longer. However, the said judgment merits consideration with respect to the fact that: (a) while the judgment recognizes the demands of maintaining taxpayer confidence by weighing these interests; (b) it only restrictively applies the good faith principle by using such words as “at the expense of” or “at least” in determining the requirements for the application of the good faith principle in an actual trial.