On January 8 and April 21, 2021, the Seoul Central District Court in South Korea issued two utterly contradictory rulings on a lawsuit for damages that had been filed by former comfort women against Japan. The issue at hand concerned the application of the rule of state immunity, where, under international law, a lawsuit can be brought against a country as a plaintiff in a foreign court, but in the absence of consent, the country cannot be judged as a defendant. Once, in the 20th century, the activities of a state extended not only to acta jure imperii (essentially, “acts of government”) but also to commercial activities, and these activities are classified as acta jure imperii and acta jure gestionis (“acts of a commercial nature”) with the principle of sovereign immunity that recognizes state immunity only over acta jure imperii becoming the mainstream.
The January decision of the Seoul Court stated that the series of acts taken by the Japanese military in the Second World War, in which it set up a comfort woman system and exposed plaintiffs to sexual assault, was a violation of jus cogens (a peremptory norm) as a crime against humanity. It stated that even if these acts were considered a country’s acta jure imperii, state immunity would not be recognized and so the court ordered Japan to pay compensation for damages to the plaintiffs.
However, the assertion that the rules of state immunity do not apply to a country’s acta jure imperii that violate a peremptory norm employed in this ruling has been repudiated by the domestic courts of many countries, including the United Kingdom, Canada, Poland, Slovenia, and New Zealand. Exceptions include the Distomo case from Greece, a case in which the plaintiff sought compensation for damages for the acts of the German armed forces in the Second World War where state immunity was not recognized (May 4, 2000), and the Ferrini case from Italy (May 11, 2004). However, in response to the Italy ruling, Germany filed an action against Italy to the International Court of Justice (ICJ), which in its judgment (February 3, 2012) clearly found the act of not recognizing state immunity as a violation of customary international law. Some years earlier in Greece the Greek Special Supreme Court repudiated the reasoning of the judgment of the Hellenic Supreme Court in the Distomo case and recognized the application of state immunity in the Lidoriki case (September 17, 2002), which involved a similar matter against the German armed forces.
With respect to acts that violate jus cogens, the April decision of the Seoul Court ruled that not recognizing state immunity even with acta jure imperii did not constitute a change to customary international law, and it dismissed the former comfort women’s case. This was a valid ruling following the present customary international law. In the ICJ’s judgment on the North Sea Continental Shelf Cases (February 20, 1969), it was determined that factual elements, or the settled state practices , and psychological elements, or opinio juris that recognizes these practices as law, are requisite for the formation of customary international law. As understood in the other domestic cases described above, general practice has not been clearly established and as such the January ruling of the Seoul Court was a breach of international law.
After the January ruling, relations between Japan and Korea plummeted to a new nadir. The Japanese government asserted that the January ruling was in violation of the Agreement on the Settlement of Problem concerning Property and Claims and on Economic Co-operation between Japan and the Republic of Korea (1965), which left the issue of the right to claim between both countries, including the comfort women issue, “settled completely and final” (Article 2). Tokyo also considered the ruling to be in violation of the mutual agreement by both Japan and South Korea that the comfort women issue was resolved “finally and irreversibly” with the Announcement by Foreign Ministers of Japan and the Republic of Korea at the Joint Press Occasion mediated by the U.S. administration of Barack Obama during South Korea’s Park Geun-hye administration.
In the case of the 2018 ruling of the Supreme Court of Republic of Korea, which recognized the right to claim compensation by former civilian workers from the Korean Peninsula for forced mobilization, the defendants were Japanese corporations that included Nippon Steel Corporation and Mitsubishi Heavy Industries, and measures were taken to confiscate the defendants’ assets in South Korea. However, in the case brought against the Japanese government by former comfort women, even if state immunity was rejected as in the January ruling and a ruling is made demanding compensation, the compulsory execution of the ruling requires the consent of Japan, and as such there is no chance of the assets of the Japanese government being confiscated. It is clear that to all that the January ruling will do no favors to bilateral relations.
In a suit in the U.S. by former comfort women seeking application of the Foreign States Immunity Act and compensation from Japan, the Supreme Court of the United States ruled that the lawsuit was an issue related to the interpretation of the Treaty of San Francisco and the Agreement on the Settlement of Problem concerning Property and Claims and on Economic Co-operation between Japan and the Republic of Korea, and that it was an issue that involved diplomatic relations with the U.S. The Court rejected the plaintiff’s suit out of respect for the opinion that the exercise of judicial jurisdiction by the U.S. Department of State could potentially have negative repercussions for U.S. foreign policy.
The courts in South Korea actively issue rulings the implications of which extend to other states that it has treaties with. In reality, rulings by domestic courts come under domestic law alone. It is part of the established international law (specifically, the Vienna Convention on the Law of Treaties, Article 27 Internal law and observance of treaties) that a country cannot invoke domestic law as grounds for justifying the non-fulfilment of a treaty. South Korea’s own rulings lead to a violation of the international law known as pacta sunt servanda (literally, “agreements must be kept,” for which see Article 26 of the Vienna Convention), which binds a government to its diplomacy. The fact that the ruling led to diplomatic issues between South Korea and Japan is a lesson. Let us hope that the April ruling will prove a first step in the transition towards a mature judicial branch in South Korea.