While what was accomplished through the Nuremberg and Tokyo tribunals, and will again be sought through the International Criminal Court (ICC) as the principal legal guardian of accountability in Ukraine, Michael Fleming’s new book, In the Shadow of the Holocaust, reminds us of another mechanism of justice: the United Nations War Crimes Commission (UNWCC). Although seldomly mentioned in the annals of war crimes prosecutions during World War II, the UNWCC’s work contributed significantly to the foundation of international law.
Established in 1943 by 17 Allied nations, the UNWCC aimed to ensure that those in the Nazi regime responsible for atrocities would be brought to justice. For example, the Moscow Declaration stated:
Those German officers and men and members of the Nazi party who have been responsible for or have taken a consenting part in the above atrocities, massacres and executions will be sent back to the countries in which their abominable deeds were done in order that they may be judged and punished according to the laws of these liberated countries and of free governments which will be erected therein.
An international criminal court would more appropriately judge major war criminals such as Himmler, Goebbels, and Göring.
Located in London, the UNWCC created a model that Allied nations could emulate when prosecuting war criminals. The commission acted as an “advisory body” to newly created national offices, and it was tasked with investigating and collecting evidence of war crimes and advising the concerned governments. In practice, after the national offices submitted a case, the UNWCC would determine whether there was prima facie evidence of a war crime; if so, the countries would be justified in apprehending and prosecuting the accused.
It was not a pointless exercise. During its existence, the UNWCC received over 36,000 cases from the national offices.
Fleming focuses primarily on Poland and its relationship with the UNWCC. This is both compelling and important. When World War II started, Poland was torn apart from two sides — invaded from the West by the German Wehrmacht and the East by the Soviet Union. After a swift military campaign and occupation, Polish citizens would soon witness unspeakable brutalities at the hand of the Nazi occupiers, and ultimately Poland would be the site of concentration camps, a horrific element of the Endlösung — Germany’s industrial attempt to exterminate the Jews of Europe. The German occupation of Poland led to the death of roughly six million Poles; nearly three million were Jews.
During the war, London became a haven for many exiled governments. The Polish one retained a vigorous yearning for justice and played a crucial role in pursuing accountability for those who committed atrocity crimes. However, its efforts were not without significant challenges, and Fleming skilfully details the Poles’ efforts in navigating the minefield of British politics.
Although some elements in the British government supported Poland’s push for accountability, as early as 1940 the Foreign Office was openly opposing the pursuit of war criminals, including those responsible for crimes committed by the Soviet Union during its occupation of Poland. The Allies wanted to avoid antagonizing Stalin, a crucial ally. Thus Poland was forced to focus on German atrocities, even though it was clear that the Soviet Union had committed them as well and had deported many Polish civilians as forced laborers to the Soviet Union.
Another reason for disharmony was the Foreign Office’s doubts about war crime trials because they had failed after World War I. David Lloyd George, prime minister during the last years of that war, had attempted to form a tribunal to try Kaiser Wilhelm II for initiating a war of aggression. Article 227 of the Treaty of Versailles provided that an international court would try him for the “supreme crime against international morality and the sanctity of treaties.” It would be the first time in history that nation-states imagined the possibility of an international criminal tribunal. But the effort fell short. Kaiser Wilhelm had fled to the Netherlands after the war and lived out his remaining years there. He was never brought to justice. 
Despite the friction, Polish officials pressed on. They saw the UNWCC as the “official forum” through which to save postwar justice. The commission obliged; it accepted the information reviewed by the Polish government regarding atrocity crimes and became an advocate for prosecutions. Its efforts were not in vain. The Polish national office submitted over 1,500 cases to the UNWCC.
Fleming tells the fascinating story of how Polish experts worked to clarify the doctrines of international criminal law and establish a legal basis for punishing Nazi Germany for the “mass murder of the European Jewry.” The Polish diplomat and future president of the International Court of Justice, Manfred Lachs, led the way in ensuring that perpetrators of those crimes would not escape judgment.
Important areas of law advanced through the UNWCC process, such as the concept of the crime against peace, that is, the planning, initiating, and waging of wars of aggression in violation of international treaties and agreements. We see the relevance of this concept today to Russia’s attack on Ukraine. The UNWCC also set the foundation for the modern legal principle of complementarity — allowing nation-states to take the lead in prosecuting alleged war criminals and recognized the need for a permanent international criminal court.
In addition, the collaborative efforts of the Polish government in exile and the UNWCC provided a blueprint for prosecuting cases of genocide and crimes against humanity.
Readers wanting a thorough examination of the roots of international criminal law, flavored with a Polish perspective, will relish this book. However, the reader should be forewarned: it is written in solid academic prose, and the sheer volume and density of information can be overwhelming. For many it will serve more as a reference book than as a page turner. But an invaluable resource it is: Fleming provides unmatched detail concerning the development of official and non-official debates for accountability in World War II and meticulously dissects the transformation of these debates into concrete action. He reminds us that international criminal law, as we know it today, was not a self-starter, and his book documents the work of men and women to whom we are in debt.
Dr. Mark Ellis is the executive director of the International Bar Association based in London.
 Mark Ellis, The Kaiser’s Trial: How a Case that Never Happened Helped Create the International Criminal Justice System, April 8, 2019, https://lareviewofbooks.org/article/the-kaisers-trial-how-a-case-that-never-happened-helped-create-the-international-criminal-justice-system/.