Peace Palace Library

10/08/2026

Start Your Research: (1) Treaties

A basic introduction to international legal research in the Peace Palace Library. Your road map for approaching an international legal research problem. Step 1.

https://peacepalacelibrary.nl/start-your-research-1-treaties

Treaty research is generally carried out first when handling an international legal research project. Article 38(1)(a) of the Statute of the International Court of Justice states that the Court shall apply 'international conventions, whether general or particular, establishing rules expressly recognized by the contesting states' as a source of law in reaching decisions. The phrase 'international conventions' is generally interpreted broadly. It is meant to include not only international conventions but all other designations, such as the word treaty that - according to the Vienna Convention on the Law of Treaties (1969) - is used for 'an international agreement concluded between States in written form and governed by international law'. Other examples are protocol, accord, act, charter, or covenant, among other instruments. While there are subtle distinctions among these designations, they may fairly be lumped together for purposes of conducting treaty research.

For conducting thorough treaty research it is important to have a solid grasp of the treaty-making process and to have an understanding of where and how to find collections of treaty documents. It is advisable to collect as much information as possible related to any particular treaty. So find the authoritative text, identify the depositary, and check the status of the treaty: identify signatories and parties to the treaty, determine the signature, ratification, acceptance, approval, accession and entry into force dates, find and read the reservations, understandings and declarations, etc.

Treaty Collections
There are different types of treaty collections that will help you to decide where to begin your treaty research project. Treaty collections may be differentiated based on their scope and coverage. They may be general, historical, national, regional, or restricted to a particular subject area. A combination of these types of treaty collections also exists. Some examples:

United Nations Treaty Series (1946- current)
League of Nations Treaty Series (1920-1946)
Consolidated Treaty Series (1648-1920)
United States Treaties and Other International Agreements (1950- current)
European Treaty Series (1949-2004)
Council of Europe Treaty Series (2004- current)

The Peace Palace Library Catalogue is your gateway to the various treaty collections. We offer access to all types of collections - electronically or in print, and cover all topics of international law. The Peace Palace Library Research Guides, prepared and maintained by our team of Law Librarians, are another powerful tool to find treaty collections. The Research Guides suggest certain collections, treaty compilations, databases and other materials considered indispensable for doing treaty law research on your specific topic.

Start Your Research ← Step 1 → Step 2

You might consider our Library Instruction on how to conduct legal research in the Library at all levels.

References
Guide to International Legal Research, Fifth Edition, Newark, LexisNexis Matthew Bender, 2003.
Hoffman, M.B. and R.C. Berring Jr., International Legal Research in a Nutshell, Second Edition, St. Paul, West Academic Publishing, 2017.
Kuehl, H.F. and M.A. O'Brien, International Legal Research in a Global Community, Durham, Carolina Academic Press, 2018.
Winer, A.S., M.A.E. Archer, and L. Louis-Jacques, International Law Legal Research, Durham, Carolina Academic Press, 2013.

09/08/2026

Event: International Day of the World's Indigenous Peoples, 9 August

The Library has a collection on this topic, see https://peacepalace.on.worldcat.org/search?sortKey=LIBRARY&databaseList=283&queryString=indigenous&changedFacet=&overrideStickyFacetDefault=&stickyFacetsChecked=on&selectSortKey=LIBRARY&overrideGroupVariant=&overrideGroupVariantValue=&scope=wz%3A45289&format=Book&subformat=Book%3A%3Abook_printbook&subformat=Book%3A%3Abook_digital&subformat=Book%3A%3Abook_thsis&subformat=Book%3A%3Abook_mic&subformat=Book%3A%3Abook_continuing&year=all&yearFrom=&yearTo=&author=all&topic=all&database=all&language=all&materialtype=all

In order to raise awareness of the needs of indigenous peoples, every 9 August commemorates the International Day of the World’s Indigenous Peoples. Especially now, they need us. Especially now, we need the tradicional knowledge, voices and wisdom of indigenous peoples.

Read more
https://www.un.org/en/observances/indigenous-day

03/08/2026

Start Your Research: (1) Treaties

A basic introduction to international legal research in the Peace Palace Library. Your road map for approaching an international legal research problem. Step 1.

https://peacepalacelibrary.nl/start-your-research-1-treaties

Treaty research is generally carried out first when handling an international legal research project. Article 38(1)(a) of the Statute of the International Court of Justice states that the Court shall apply 'international conventions, whether general or particular, establishing rules expressly recognized by the contesting states' as a source of law in reaching decisions. The phrase 'international conventions' is generally interpreted broadly. It is meant to include not only international conventions but all other designations, such as the word treaty that - according to the Vienna Convention on the Law of Treaties (1969) - is used for 'an international agreement concluded between States in written form and governed by international law'. Other examples are protocol, accord, act, charter, or covenant, among other instruments. While there are subtle distinctions among these designations, they may fairly be lumped together for purposes of conducting treaty research.

For conducting thorough treaty research it is important to have a solid grasp of the treaty-making process and to have an understanding of where and how to find collections of treaty documents. It is advisable to collect as much information as possible related to any particular treaty. So find the authoritative text, identify the depositary, and check the status of the treaty: identify signatories and parties to the treaty, determine the signature, ratification, acceptance, approval, accession and entry into force dates, find and read the reservations, understandings and declarations, etc.

Treaty Collections

There are different types of treaty collections that will help you to decide where to begin your treaty research project. Treaty collections may be differentiated based on their scope and coverage. They may be general, historical, national, regional, or restricted to a particular subject area. A combination of these types of treaty collections also exists. Some examples:

United Nations Treaty Series (1946- current)
League of Nations Treaty Series (1920-1946)
Consolidated Treaty Series (1648-1920)
United States Treaties and Other International Agreements (1950- current)
European Treaty Series (1949-2004)
Council of Europe Treaty Series (2004- current)

The Peace Palace Library Catalogue is your gateway to the various treaty collections. We offer access to all types of collections - electronically or in print, and cover all topics of international law. The Peace Palace Library Research Guides, prepared and maintained by our team of Law Librarians, are another powerful tool to find treaty collections. The Research Guides suggest certain collections, treaty compilations, databases and other materials considered indispensable for doing treaty law research on your specific topic.

You might consider our Library Instruction on how to conduct legal research in the Library at all levels.

References

Guide to International Legal Research, Fifth Edition, Newark, LexisNexis Matthew Bender, 2003.

Hoffman, M.B. and R.C. Berring Jr., International Legal Research in a Nutshell, Second Edition, St. Paul, West Academic Publishing, 2017.

Kuehl, H.F. and M.A. O'Brien, International Legal Research in a Global Community, Durham, Carolina Academic Press, 2018.

Winer, A.S., M.A.E. Archer, and L. Louis-Jacques, International Law Legal Research, Durham, Carolina Academic Press, 2013.

06/07/2026

Start Your Research

A basic introduction to international legal research in the Peace Palace Library. Your road map for approaching an international legal research problem. Step 1-11.

https://peacepalacelibrary.nl/start-your-research

For thorough and complete public international legal research, six sources of law must be consulted. Please, be aware that these sources are categorized as either primary sources, subsidiary sources of law, or peremptory norms. Start by following the structure of Article 38 of the Statute of the International Court of Justice: (1) treaties, (2) custom, and (3) general principles of law. Subsidiary sources include (4) judicial decisions and the (5) writings of highly qualified publicists. And last, you should consider (6) peremptory norms of international law (jus cogens) which are so fundamental as no derogation from them is permitted.

Continue your search with (7) resolutions and decisions of international organizations. Although they cannot themselves constitute international law or serve as conclusive evidence of a rule of customary law, such resolutions do have value in providing evidence of existing or emerging law. Focus your research on the actions of the United Nations and its various organs. The concept of (8) soft law presents another opportunity for further research as it plays a role in the development of international law. It may become binding when it is incorporated explicitly into an international treaty or otherwise hardens into customary international law.

Once you’ve finished your research on the sources of law, it is time to consult (9) secondary sources for background information and context. Secondary sources are resources that explain, analyze, synthesize, critique or comment on the law. There are a variety of types of secondary sources, including: books, essays, journal articles, dictionaries, legal encyclopedias, law reports, legal treatises, practice materials, blogs, and newspapers.

You should consider the extensive (10) library services the Peace Palace Library has to offer. With so much information available, we are committed to assisting and facilitating your research in public international law, through the website, and with a personal touch. Our (11) law librarians are at your service. They will use innovative search strategies to take knowledge where it’s needed: You!

30/06/2026

Event: International Day of Parliamentarism, 30 June

The Library has a collection on this topic, see https://peacepalace.on.worldcat.org/search?databaseList=283&queryString=parliament

What parliaments do
Strong parliaments are a cornerstone of democracy. They represent the voice of the people, pass laws, allocate funds to implement laws and policies, and hold governments to account. They work to make sure that policies benefit all people, especially the most vulnerable.

Parliaments also link international and national agendas, ensuring that governments implement international treaties and agreements that they sign up to. They play a vital role in implementing the 2030 Agenda for Sustainable Development, and the Inter-Parliamentary Union (IPU) has been working closely with them to help build their capacity in doing so.

In countries emerging from conflict, robust parliaments can help make possible a peaceful transition to a functioning democracy by healing divisions in society through dialogue and cooperation.

Read more
https://www.un.org/en/observances/parliamentarism-day

26/06/2026

Event: International Day in Support of Victims of Torture, 26 June.

The Library has a collection on this topic, see https://peacepalace.on.worldcat.org/search?sortKey=LIBRARY&databaseList=283&queryString=torture&changedFacet=&overrideStickyFacetDefault=&stickyFacetsChecked=on&selectSortKey=LIBRARY&overrideGroupVariant=&overrideGroupVariantValue=&scope=wz%3A45289&format=Book&subformat=Book%3A%3Abook_printbook&subformat=Book%3A%3Abook_digital&subformat=Book%3A%3Abook_thsis&year=all&yearFrom=&yearTo=&author=all&topic=all&database=all&language=all&materialtype=all

Torture: a crime against humanity
Torture seeks to annihilate the victim’s personality and denies the inherent dignity of the human being. Despite the absolute prohibition of torture under international law, torture persist in all regions of the world. Concerns about protecting national security and borders are increasingly used to allow torture and other forms of cruel, degrading and inhuman treatment. Its pervasive consequences often go beyond the isolated act on an individual; and can be transmitted through generations and lead to cycles of violence.

Read more
https://www.un.org/en/observances/torture-victims-day

24/06/2026

We thank Felix Weinlinger, our 5th Austrian peace servant, for the wonderful work he has done this year in our Library. He will return to Austria to continue his studies and we wish him all the best!!! 📚👨🏼‍🎓🇦🇹 PPL Staff

22/06/2026

Start Your Research: (11) Our Law Librarians

A basic introduction to international legal research in the Peace Palace Library. Your road map for approaching an international legal research problem. Step 11.

https://peacepalacelibrary.nl/our-staff

We are committed to assisting and facilitating your research in public international law, through the website, and with a personal touch. Our Law Librarians are at your service. They will use innovative search strategies to take knowledge where it’s needed: You!

21/06/2026

Research Guide
The Tokyo Trial (updated)

https://peacepalacelibrary.nl/research-guide/tokyo-trial

Twenty-eight Japanese military and political leaders were charged in the Tokyo Trial with fifty-five separate counts encompassing the waging of aggressive war, murder and conventional war crimes committed against prisoners-of-war, civilian internees and the inhabitants of occupied territories. The defendants included former prime ministers, former foreign ministers and former military commanders. In the course of the proceedings, the court ruled that 45 of the counts, including all the murder charges, were either redundant or not authorized under the IMTFE Charter.

Following months of preparation, the IMTFE convened first on April 29, 1946. The trials were held in the War Ministry office in Tokyo. On May 3 the prosecution opened its case, charging the defendants with crimes against peace, conventional war crimes, and crimes against humanity. The trial continued for more than two and a half years, hearing testimony from 419 witnesses and admitting 4,336 exhibits of evidence, including depositions and written statements from 779 other individuals.

Following the model used at the Nuremberg trials in Germany, the Allies established three broad categories. "Class A" charges, alleging crimes against peace, were to be brought against Japan's top leaders who had planned and directed the war. Class B and C charges, which could be leveled at Japanese of any rank, covered conventional war crimes and crimes against humanity, respectively. Unlike the Nuremberg trials, the charge of crimes against peace was a prerequisite to prosecution - only those individuals whose crimes included crimes against peace could be prosecuted by the Tribunal.

Sentencing

After the defense had finished its presentation on September 9, 1947 the IMT spent fifteen months reaching judgment and drafting its 1,781-page opinion. The reading of the judgment and the sentences lasted from December 4 to 12, 1948. Five of the eleven justices released separate opinions outside the court.

One defendant, Shūmei Ōkawa, was found mentally unfit for trial and the charges were dropped. Two defendants, Yōsuke Matsuoka and Osami Nagano, died of natural causes during the trial. Six defendants were sentenced to death by hanging for war crimes, crimes against humanity, and crimes against peace (Class A, Class B and Class C): General Kenji Doihara, chief of the intelligence services in Manchukuo, Kōki Hirota, prime minister (later foreign minister), General Seishirō Itagaki, war minister, General Heitarō Kimura, commander, Burma Area Army, Lieutenant General Akira Mutō, chief of staff, 14th Area Army, General Hideki Tōjō, commander, Kwantung Army (later prime minister). One defendant was sentenced to death by hanging for war crimes and crimes against humanity (Class B and Class C): General Iwane Matsui, commander, Shanghai Expeditionary Force and Central China Area Army. They were executed at Sugamo Prison in Ikebukuro on December 23, 1948. MacArthur, afraid of embarrassing and antagonizing the Japanese people, defied the wishes of President Truman and barred photography of any kind, instead bringing in four members of the Allied Council to act as official witnesses.

Sixteen defendants were sentenced to life imprisonment. Three (Koiso, Shiratori, and Umezu) died in prison, while the other thirteen were paroled between 1954 and 1956. Foreign minister Shigenori Tōgō was sentenced to 20 years' imprisonment. Togo died in prison in 1949. Foreign minister Mamoru Shigemitsu was sentenced to 7 years. He later served as Foreign Minister and as Deputy Prime Minister of post-war Japan.

Research Guide

This Research Guide is intended as a starting point for research on the Tokyo Trial. It provides the basic legal materials available in the Peace Palace Library, both in print and electronic format. Handbooks, leading articles, bibliographies, periodicals, serial publications and documents of interest are presented in the Selective Bibliography section. Links to the PPL Catalogue are inserted. The Library's subject heading (keyword) International Military Tribunal for the Far East is instrumental for searching through the Catalogue. Special attention is given to our subscriptions on databases, e-journals, e-books and other electronic resources. Finally, this Research Guide features links to relevant websites and other online resources of particular interest.

Research guide on the International Military Tribunal for the Far East (Tokyo Trial) prosecuting the leaders of the Empire of Japan after World War II.