On July 4, 2025, France’s highest court convened in plenary session to hear arguments on whether an arrest warrant against Bashar al-Assad, issued while he was President of Syria, violates head of state immunity. Following the oral arguments, the court announced it would deliver its judgment on July 25, 2025. The international arrest warrant was issued for al-Assad’s alleged role in the infamous August 2013 chemical weapons attacks that killed over 1,400 civilians in Douma and al-Ghouta, Syria. The warrant was issued by French investigating judges in November 2023, following a complaint by survivors and NGOs. While France’s National Anti-Terrorism Prosecutor has challenged al-Assad’s warrant on immunity grounds, the Paris Court of Appeals confirmed its validity in June 2024. The Cour de Cassation’s upcoming decision will address fundamental questions about the scope of immunity for international crimes. One of us (Kostas) is a lawyer who supported Syrian victims and NGOs to build and litigate the case, and the other (Plesch) submitted an expert opinion in the case showing how questions of head of state immunity were addressed over seventy years ago—precedents that have been largely forgotten but should fundamentally inform any analysis of the legal issue.
The ICJ’s Incomplete Foundation
The Prosecutor’s position that sitting heads of state enjoy absolute immunity relies heavily on the International Court of Justice’s 2002 Arrest Warrant judgment, which examined state practice and found “it has been unable to deduce from this practice that there exists under customary international law any form of exception to the rule according immunity from criminal jurisdiction and inviolability to incumbent Ministers of Foreign Affairs, where they are suspected of having committed war crimes or crimes against humanity.” This finding has been widely interpreted as establishing absolute personal immunity for the “troika”—heads of state, heads of government, and foreign ministers—before foreign domestic courts.
However, this interpretation rests on a fundamentally flawed foundation. The ICJ’s analysis did not consider extensive state practice from 1943-1948 that directly contradicts this view—practice that remained classified and largely inaccessible until 2014 due to Cold War-era political pressures.
The Lost Archives and Their Revelations
The missing evidence lies in the archives of the United Nations War Crimes Commission (UNWCC), established in 1943 by sixteen Allied states including France. After World War II ended, geopolitical pressures led to the classification of the entire archive in 1949. Only in 2014, following advocacy efforts, did the U.S. Holocaust Memorial Museum make a complete copy of the UNWCC archives available to the public.
These records reveal a comprehensive rejection of head of state immunity for international crimes that fundamentally challenges conclusions reached in the Arrest Warrant judgment.
State Practice: Hitler’s Indictments While Head of State
The archives document that between November 1944 and April 1945, three Allied states brought detailed criminal charges against Adolf Hitler while he served as Germany’s head of state:
Czechoslovakia filed eleven separate charges covering crimes at Lidice, Dachau, Buchenwald, and Terezin, citing violations of the Hague Conventions and Czechoslovak criminal law. The charges ranged from establishing illegal courts and mass murder to forced labor and systematic terrorism.
Poland charged Hitler with the “biological extermination of the Jews in Poland,” invoking the Fourth Hague Convention of 1907 and Polish national war crimes decrees.
Belgium brought charges related to atrocities at Auschwitz and Buchenwald under Belgian domestic criminal law.
Each indictment was reviewed by the UNWCC’s Committee on Facts and Evidence, which determined they met the prima facie standard for prosecution. Hitler’s name subsequently appeared on official UNWCC lists of war criminals subject to arrest and trial in domestic courts—a sitting head of state formally designated for prosecution by foreign domestic jurisdictions.
The Legal Framework Behind Rejection of Head of State Immunity
The UNWCC’s rejection of head of state immunity was not an ad hoc political decision but a carefully considered legal determination. The Commission appointed a special subcommittee in December 1944, chaired by Lord Wright, to study the question of head of state immunity “in all its details.” After careful analysis of Nazi governmental structures and individual responsibility, the subcommittee reached a clear conclusion.
As documented in the UNWCC’s official History, published in 1948 and representing the collective views of all member states:
“The Commission and its Committee on Facts and Evidence adopted the rule of placing such persons on war crimes lists, and consequently rejected as irrelevant the doctrines of immunity of heads of State and members of Government, and of acts of State. Upon charges presented by various nations, Hitler was placed on the Lists of war criminals on several occasions, and so were other high State administrators, such as Mussolini.”
This finding was based on the Commission’s assessment that meaningful accountability for international crimes required rejection of traditional immunity doctrines. The History explains that if accountability for such grave crimes was to be more than “theoretical, moral, or political condemnation,” it “could be done only by dismissing the doctrine of immunity of heads of state.”
France’s Central Role
France played a foundational role in establishing this precedent. General Charles de Gaulle signed the 1942 St. James Declaration endorsing prosecution of war criminals “whether they have ordered them, perpetrated them or participated in them”—language that explicitly excluded no one based on rank or position. Professor André Gros, representing France at the crucial September 1944 UNWCC meeting, supported Hitler’s inclusion on the war criminals list.
This position built on France’s earlier advocacy following World War I. The 1919 Commission on Responsibilities, to which France contributed two members, adopted a report rejecting head of state immunity, stating that “there is no reason why rank, however exalted, should in any circumstances protect the holder of it from responsibility.” France advanced the position that immunity “depends on whether the sovereign in question conducted himself as a law-abiding and trustworthy chief of state” and that by committing serious violations of international law, “a sovereign loses … any immunity he might claim under international law.”
The Commission’s Reasoning and Contemporary Relevance
The UNWCC’s analysis addressed the evolving nature of international crimes and their impact on traditional immunity concepts. The Commission reasoned that developments in crimes against peace and crimes against humanity “brought about profound alterations in the doctrines of immunity of heads of State” and “individual responsibility of members of Governments and high-ranking administrators.”
The Commission explicitly linked the rejection of immunity to the principle of non-impunity for grave crimes:
“If the proposition that aggressive wars or persecutions on racial, political, or religious grounds in time of war were criminal acts, was not to be confined to the sphere of moral principles … the only way to deal with it was to recognise that individuals upon whose decisions such acts depended were to be held penally responsible. This could be done only by dismissing the doctrine of immunity of heads of state.”
Evidence of Consensus and Legal Authority
The UNWCC’s position reflected not merely the views of a few states but enjoyed broad support within the international community. The Commission’s work was endorsed by sixteen Allied nations representing the major powers and numerous smaller states. The legal authority of this consensus is demonstrated by the subsequent Nuremberg and Tokyo Charters, which explicitly rejected immunity for heads of state and government officials.
Article 7 of the Nuremberg Charter declared: “The official position of defendants, whether as heads of State or responsible officials in Government departments, shall not be considered as freeing them from responsibility or mitigating punishment.” This principle was subsequently incorporated into Control Council Law No. 10 and has influenced international criminal law development ever since. None of the states supporting an international tribunal for prosecution of WWII’s major war criminals considered that such a tribunal was necessary to overcome personal immunity of the troika.
Implications for the al-Assad Case
The rediscovered UNWCC practice should inform the Cour de Cassation’s analysis of immunity in the al-Assad case. Rather than the Arrest Warrant judgment’s finding of no relevant state practice, the evidence reveals extensive, coordinated state practice during the formative period of international law explicitly rejecting head of state immunity for international crimes.
The chemical weapons attacks at Douma and al-Ghouta involved sarin, a nerve agent specifically prohibited under the Chemical Weapons Convention. The systematic nature of these attacks, combined with their targeting of civilian populations, places them squarely within the category of crimes that the international community has determined cannot be shielded by immunity. Reflecting the gravity of these crimes, the UN Security Council (unanimously), UN General Assembly, and OPCW called for all perpetrators of these attacks to be held accountable.
The Path Forward
The Cour de Cassation now faces a choice between perpetuating the incomplete analysis of the Arrest Warrant case or recognizing the full scope of relevant state practice. The WWII foundation demonstrates that even during the 1940s, the international community recognized that certain crimes are of such gravity that traditional immunity concepts cannot shield perpetrators from accountability.
France, as a founding member of the UNWCC and a leader in establishing the principle of accountability over immunity, has the opportunity to place this precedent in its rightful place in international law. By recognizing that head of state immunity cannot protect those responsible for chemical weapons attacks against civilian populations, the court can honor both historical precedent and contemporary legal principles demanding accountability for the gravest crimes.
The question is not whether al-Assad committed the alleged crimes—that determination awaits trial. Rather, it is whether any individual, regardless of position, can claim immunity from prosecution for systematic attacks using prohibited chemical weapons against civilian populations. The answer, established through extensive state practice over seventy years ago but hidden by Cold War politics, remains clear: justice must prevail over impunity.
