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The Gaps in Japanese Maritime Security Law and the Senkaku Situation

Issues & Insights Vol. 21, SR 2, pp. 12-15

Volume Overview

“The Gaps in Japanese Maritime Security Law and the Senkaku Situation” is the second chapter of Issues & Insights Vol. 21, SR 2 — Advancing a Rules-Based Maritime Order in the Indo-Pacific. Authors of this volume participated in the Indo-Pacific Maritime Security Expert Working Group’s 2021 workshop that took place, virtually on March 23-24. The working group, composed of esteemed international security scholars and maritime experts from Japan, the United States, and other Indo-Pacific states, was formed to promote effective U.S.-Japan cooperation on maritime security issues in the region through rigorous research on various legal interpretations, national policies, and cooperative frameworks to understand what is driving regional maritime tensions and what can be done to reduce those tensions. The workshop’s goal is to help generate sound, pragmatic and actionable policy solutions for the United States, Japan, and the wider region, and to ensure that the rule of law and the spirit of cooperation prevail in maritime Indo- Pacific.

Chapter Excerpt


This paper addresses the legal and operational gaps in Japanese law to defend its remote islands and the challenges that the U.S.-Japan alliance will encounter in the Senkaku situation.

Japan incorporated the Senkaku Islands in 1895, which were, according to the Japanese government, terra nullius at that time. However, China started to claim sovereignty in 1971enacted the Law on the Territorial Sea and the Contiguous Zone in 1992, specifying the islands as a part of its territory. Since 2008, China has been regularly sending government ships to Senkaku Islands’ waters to assert that they belong to China. These vessels stay and hover for several hours, interfering with the activities of Japanese fishing vessels. The intensity of these activities increased after September 2012, when the Japanese government bought the islands from their owner. In addition, China has been using maritime militia posing as ordinary fishing boats, creating a situation where there are increased threats to Japanese security, but Chinese official responsibility is not evident.

While maritime security threats posed by the dispute over the Senkaku Islands are nothing new, the level of intensity has reached a new high with the implementation of the Chinese Coast Guard (CCG) Act of 2021. This law authorizes the CCG to operate in contravention of the United Nations Convention on Law of the Sea (UNCLOS). There are three primary issues regarding the CCG Act from an international law perspective.

The first issue is that the law claims more than what China can justify under UNCLOS, and as a result, the freedom of the seas that every state enjoys is placed in jeopardy. The second issue is that the law may justify the CCG to take coercive measures potentially beyond what is permissible under international law. Lastly, the law obliges the CCG to “protect” its “maritime boundary” and monitor activities on the high seas and foreign EEZs. CCG conduct based on this act would contravene international law, and the establishment of the CCG Act increases the risk of a standoff between the CCG, Japan Coast Guard (JCG), and Japan Maritime Self Defense Force (JMSDF).

Article 21 of the CCG Act is particularly pertinent to the Senkaku situation. It provides that “if foreign warships and foreign government ships used for non-commercial purposes that violate Chinese law and regulations in the jurisdictional maritime water, the CCG has the right to take necessary warning and control measures to stop them, and order them to leave the water immediately.” Furthermore, “for those who refuse to leave and cause serious harm or threats, the CCG has the right to take measures such as forced towing and eviction.” The “jurisdictional maritime water” includes not only the internal water and territorial sea but also the exclusive economic zone (EEZ), continental shelf and “other maritime areas over which China has jurisdiction.” UNCLOS Article 31 provides “[i]f any warship does not comply with the laws and regulations of the coastal State concerning passage through the territorial sea and disregards any request for compliance therewith which is made to it, the coastal State may require it to leave the territorial sea immediately.” Yet, CCG Act Article 21 authorizes the agency to use coercive measures which may violate the sovereign immunity that foreign warships and government ships used for non-commercial purposes enjoy in a foreign territorial sea. For China, it would include a JCG vessel entering into the Senkaku Islands’ territorial sea. Furthermore, CCG Act Article 21 governs the jurisdictional maritime area instead of the territorial sea and covers government ships. To implement this provision beyond its territorial sea is an infringement of the freedom of the seas and the sovereign immunity of government vessels provided under UNCLOS Articles 87(1), 95, and 96.

Because China has a new administrative law to provide the basis for CCG conduct, it will likely strengthen and justify what the CCG can do in the territorial waters of disputed features and undelimited areas in the East China Sea. This paper addresses the legal and operational gaps in Japanese national security law in light of the new Chinese law. It will specifically address (1) the gaps between Maritime Security Operation order and Defense Operation order, (2) the challenges to coordination between JCG and JSMDF, and (3) the effect of these gaps on Japan-U.S. Alliance and cooperation from an international law perspective. Since this paper focuses on the legal perspective, it primarily discusses the first point.

The main finding of this paper is that these gaps are inherent in the structure of the Japanese national security law. To overcome the gaps and protect Japan’s remote islands, seamless coordination between JCG and JSMDF and deeper cooperation between Japan and the U.S. are necessary.

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Yurika Ishii is an Associate Professor at the National Defense Academy of Japan, Graduate School of Security Studies, where she is in charge of the law of the sea and public international law courses.

The Indo-Pacific Maritime Security Expert Working Group’s 2021 workshop and this volume were funded by a grant from the U.S. Embassy Tokyo, and implemented in collaboration with the Yokosuka Council on Asia Pacific Studies (YCAPS).

The statements made and views expressed are solely the responsibility of the authors and do not necessarily reflect the views of their respective organizations and affiliations. For questions, please email [email protected].

Photo: The number of China Coast Guard and other vessels that entered Japan’s contiguous zone or intruded into the territorial sea surrounding the Senkaku Islands as compiled by Japan Coast Guard. Source: Screenshot from the website of the Ministry of Foreign Affairs, Japan.