법정지법의 적용에 있어서 절차와 실체의 구분

The Supreme Court ruled that judgment interest as set forth in the Act on Acceleration of Civil Procedure is substantive in nature. Therefore, judgment interest should be applied only when the governing law applicable to the case is Korean law. Since the governing law of the above Supreme Court case was Japanese law, the Court rejected the application of Korean law and, instead, applied the Japanese law analogous to the Korean law. Of note, the interest rate as dictated by the Korean law is much higher than the interest rate dictated by the Japanese law. The Supreme Court ruling raises a question that has been rarely discussed in Korea, but hotly discussed in foreign countries. The question is how to distinguish between procedure and substance. As recognized in most countries, lex fori is mandatorily applied to civil procedures regardless of lex causae. Judgment interest has elements of both procedure and substance, which is clearly recognized by the Court. Besides judgment interest, we can easily find many other examples that are both procedural and substantive in nature. Thus, the criteria to determine what is procedure or substance is very important. Despite this the Court ruling does not give a clear-cut answer to this question. This article discusses the above issue based on the Supreme Court ruling as well as foreign cases and discussions.