조세조약의 해석과 적용―비엔나협약의 관점에서―

The Vienna Convention is applies to the interpretation of tax treaties under close relationship with Article 3, Paragraph 2 of the OECD Model Tax Convention. According to Article 31 of the Vienna Convention, a treaty shall be interpreted in good faith in accordance with the ordinary meaning given to the terms of the treaty in their context including the preamble and annexes, and in the light of its object and purpose. Subsequent agreement, subsequent practice and relevant rules of international law shall also be taken into account., together with the context. According to Article 32 of the above Convention, when interpreting a treaty, in certain cases, supplementary means of interpretation, including the preparatory work of the treaty and the circumstances of its concludion, may be relied upon. The results of a review of several issues in the tax treaty, focusing on the interpretation standards of the Vienna Convention as above, are as follows. First, it is difficult to conclude that the interpretation of tax treaties under Articles 31 and 32 of the Vienna Convention and the strict interpretation recognized for our domestic tax laws are the same. Rather, there is considerable room for the interpretation of tax treaties under the Vienna Convention to be viewed as more flexible than the strict interpretation. Second, if a term that is not defined in a tax treaty has a common meaning that can be evaluated as constituting the content of the treaty, it takes precedence over the meaning under domestic law. However, in other cases, it is reasonable to consider that the meaning under domestic law takes precedence. Supreme Court decision 2016du42883, delivered on December 27, 2018, refused to take the interpretaion of ‘use of patent rights’, which is not defined under the Korea-US tax treaty based on the second sentence in the proviso of Article 93, Paragraph 9 of the former Corporate Tax Act on the grounds of the ordinary meaning of exists under the Patent Act. However, there is room to view it differently. Third, the 2018du54408 decision of the Supreme Court, pronounced on July 21, 2021, ruled, taking into various circumstances that ‘accounting period for which the distribution of profit takes place’ prescribed in Article 10, Paragraph 2 (a) of the Korea-Japan Tax Treaty meant ‘the accounting period subject to dividends’ rather than the ‘accounting period to which the resolution date belongs’, which took a different interpretation from what the ordinary meaning dictates, taking into account the context, object and purpose of the relevant treaty, good faith principles, or subsequent practice. This is an example showing that the function of ordinary meaning in the interpretation of tax treaties under the Vienna Convention may be partially limited depending on the interaction with other elements of interpretation. Fourth, since general mutual agreements do not concern matters delegated with a specific scope determined by a tax treaty, it is difficult for them to be recognized as legally binding. However, a general mutual agreement is a subsequent agreement pertaining to Article 31, Paragraph 3 (a) of the Vienna Convention, and should be respected in principle if made within the scope of possible interpretation of the tax treaty, so it is in fact in a similar position to a binding rule. Even in accordance with the OECD Model Convention revised in 2017, making a mutual agreement on terms not defined in the tax treaty, different from the meaning of existing domestic law, where such terms are already supplemented by domestic law, constitutes a revision of the tax treaty. Since the subject of a mutual agreement generally does not have the authority to represent the state, and it is difficult to expect the mutual agreement to go through the treaty amendment process, such as the consent of the National Assembly, a mutual agreement that is different from the meaning of domestic law should generally be regarded as invalid. Fifth, reciprocity under international law can be considered in the interpretation and application of tax treaties as a ‘relevant rules of international law’ under Article 31, Paragraph 3 (c) of the Vienna Convention. Such examples include ① delimitation of the scope of application or the function of a balance between domestic law and the tax treaty context under Article 3, Paragraph 2 of the OECD Model Treaty, ② burden of proof of domestic source income, and ③ treaty exclusion.