Regarding the critique of J. Y. Interpretation No. 748 from methodological viewpoint, the author did it before. This article is to explore the binding of this interpretation based on the assumption of its validity. The article will discuss relevant theories and practice in Taiwan and Germany, and refer to the jurisprudence in the Anglo-American law, including its distinction between ratio decidendi and obita dicta. In addition to analyzing the general questions on the binding of J. Y. Interpretation, this article will also discuss the specific content of J. Y. Interpretation No. 748 and the possible influence of the binding of the legislature/referendum.