The French Cour de Cassation, on Friday, annulled an arrest warrant against the former president of Syria, Bashar Al-Assad, holding that sitting foreign leaders are immune from prosecution.

On the question of whether an exception would exist in the event of crimes against humanity and war crimes, the court rejected both the argument that an immunity would cease due to such acts falling outside the exercise of the function of a “Head of State-In-Office” and the notion that peremptory norms (jus cogens) based on Article 53 of the Vienna Convention 1969 would override the immunity.

This means that no country is allowed to prosecute a head of state under its criminal jurisdiction; the Cour de Cassation underscored that “immunity does not equate to impunity.” Nevertheless, such an individual could still be prosecuted through alternative avenues, such as a trial in their own country or the country where the alleged war crime had been committed.  The principle does not apply to international jurisdiction, such as the International Criminal Court, which expressly excludes such immunity under Article 27 of the Rome Statute.

Regarding the time beyond the period in office, such as in the case of Al-Assad, who currently holds asylum in Russia, individuals would only benefit from immunity from acts within the function of a head of state, allowing for prosecution for war crimes within any country’s criminal justice system post-factum of office occupancy.

The warrant, issued in 2023, was quashed due to the immunity of heads of state under French law; a renewed warrant, issued in 2025, is still in force against the ousted president.

On November 14, 2023, an arrest warrant was issued by the French judiciary against the former Syrian president in response to attacks against the opposition-controlled Damascus suburbs of Eastern and Western Ghouta using chemical nerve agents during the Syrian civil war in 2013. Shortly after, the French National Anti-Terrorist Public Prosecutor’s Office requested that the warrant be annulled due to the immunity of heads of state. In response, in a judgment of June 2024 by the Paris Court of Appeal, the warrant was affirmed on appeal.

On renewed appeal by the prosecutor-general on June 26, 2024, the court clarified the extent to which personal immunity applies to “Heads of State-In-Office,” to “protect a sovereign State from any foreign interference.” The court noted that, based on the UN Declaration concerning Friendly Relations and Co-operation among States and Article 29 of the Vienna Convention on Diplomatic Relations, a head of state is customarily immune from any form of arrest or detention, thereby upholding the equality of member states in the international community. This immunity is not contingent on recognition of the person’s legitimacy by other countries.

While the judgement, based on the immunity granted to a head of state, annulled the 2023 warrant, a second French arrest warrant for barrel bombing against civilians in 2017, issued in January 2025 after Assad’s flight to Moscow, is not affected by the Supreme Court’s judgement. Followingly, any further warrants for crimes against humanity, such as the 2013 chemical weapons attacks, can be issued by authorities.