AcademicsFaculty Information


Associate Professor
Doctor of Laws (Kyushu University)
Office:Room No. 513
Office Hours:
Link to Research Map:​


After working at several universities, Japan Coast Guard Academy, Ministry of Foreign Affairs of Japan (Consulate-General of Japan at Hamburg) and the foundation, for the specialist of public international law, and then becoming the member of the EUH. For detailed information, please see the website of “researchmap”.

Academic Field / Expertise

Public International Law

Courses to Offer

Legal Mind


We may not always be conscious of it, but our lives are always supported by the Law. More than we realise, the Law provides a framework for our daily lives and protects us. As the Showa, Heisei and Reiwa eras has progressed, the values of people are changing. And now we are expected to respect diversities and to collaborate with others. The requirements of this new society must be met by a new social framework or law (i.e., Neque mittunt vinum novum in utres veteres). As Japan and the world seek for the new society, problem-solvers are in demand. My lecture gives you the chance to challenge various new problems together using the Law.

Summary of the Research Undertaken

My main research interest is the legal evaluation of the unilateral acts of States using materials on the law of the sea and diplomatic documents.

Research Themes

  • Protest in International Law and its Legal Effect
  • Development of Artificial Intelligence on Diplomatic Document Data Analysis
  • Expansion on Utilisation of Diplomatic Document Data in International Law and Diplomatic Studies

Details of the Research

Just as the conduct of individuals is evaluated by the Law in domestic societies, the conduct of States is also evaluated by the Law in international societies. In making this legal evaluation, the act in question will be examined on the basis of evidence.


In my doctoral thesis, I examined the correctness of the appraisals of the unilateral acts of States in international law in the past, using the example of the conduct of States in the field of the law of the sea. The results show that the commonly accepted appraisal of unilateral act is not rightly reflected the actual conduct of the States and in order to properly evaluate a state's conduct, it is necessary to examine an enormous amount of diplomatic documents, which is beyond human control.


As a solution, my current research is pursuing the use of artificial intelligence to help. The social implementation of artificial intelligence is progressing at a rapid pace, but its use in the field of legal research has not progressed. The reason for the lack of use in the field of legal research is the lack of basic understanding of techniques for artificial intelligence on the part of legal scholars and the lack of understanding of the methodology of legal research on the part of technologists. My current research is sure to be a bridge between these two gaps in understanding.

List of Papers

  • NAGAOKA, Sakura, “Artificial Intelligence and Human Rights: Legal Significance of Artificial Intelligence Principles”, Reports of Comprehensive Research Organization, Fukuoka Institute of Technology, vol.4 (2021), pp.85-89 (in Japanese).
  • NAGAOKA, Sakura, “Research on International Law and Artificial Intelligence Technology: Towards the Utilisation of Diplomatic Documents”, The Kyushu Law Association Journal 2019 (2019), pp.40-43 (in Japanese).
  • NAGAOKA, Sakura, “Protest in International Law and its Transformation: Freedom of Navigation Program of the United States”, Reports of Environments Research Laboratory, Fukuoka Institute of Technology, vol.9 (2015), pp.67-75 (in Japanese).
  • NAGAOKA, Sakura, “The Regime of the Continental Shelf in International Law”, Kanrin: Bulletin of the Japan Society of Naval Architects and Ocean Engineers (Kanrin: Nihon Kaiyo Senpaku Kogakkai Shi), vol.52 (2014), pp.9-18 (in Japanese).
  • NAGAOKA, Sakura, “Japan-China’s Assertions concerning the Baselines around the Senkaku Islands”, The Journal of Island Studies, vol.3-1 (2013), pp.106-117 (in Japanese).


Key Words of the Research

Public International Law, Unilateral Acts of States, Law of Treaties, International Law of the Sea, Dispute Settlement, Diplomatic Documents, Artificial Intelligence, Diplomatic Studies, Artificial Intelligence Technology, Data Analysis

Related SDGs
  • 産業と技術革命の基盤をつくろう
  • 海の豊かさを守ろう
  • 平和と公平をすべての人に
  • パートナーシップで目標を達成しよう