Symposium on Prosecuting Heads of State for International Crimes: Immunities of Heads of State before International Criminal Law Proceedings

[Diane A. Desierto is full Professor of Law at the University of Notre Dame’s Law School, the Faculty Director of the LLM Program in International Human Rights Law, and Founding Director of the Notre Dame Law School Global Human Rights Clinic.]

Heads of State can attempt to assert their traditional immunities and privileges before international criminal court proceedings, but they will find that States themselves already waived such immunities of incumbent or former Heads of State in advance, when States entered into treaties that created and designed many of today’s modern international courts and tribunals.

In crafting rules waiving or diminishing Head of State immunities in international criminal court proceedings, it should be noted that States relied heavily on the vast scope of traditional immunities and privileges of Heads of State against civil and criminal lawsuits brought against Heads of State in the courts of other States. The orthodox position was that the immunity of the Head of State from any civil or criminal jurisdiction of courts in other States operated to preserve diplomatic relations, international comity, and sovereign equality. Thus, while in office, Heads of State generally enjoy personal immunity against suits before domestic courts of another State for acts committed by Heads of State in the performance of their official functions. In this status, the Head of State’s immunity plea is most similar to the plea of State immunity itself against civil lawsuits brought against the State in foreign courts. While Heads of State might be distinguishable in some constitutional monarchies from Heads of Government (and both are presumed to have full powers to conclude as well as terminate treaties on behalf of the State), their claim of personal immunity from foreign or international legal process is relatively analogous to Article 39(2) of the 1961 Vienna Convention on Diplomatic Relations. Article 3(2) of the 2004 United Nations Convention on the Jurisdictional Immunities of States and their Properties purposely recognizes the privileges and immunities accorded under international law “to heads of State ratione personae”.

A serving Head of State that is in office or in the performance of official functions ordinarily enjoys complete inviolability and absolute immunity from criminal jurisdiction before the courts of another State, with national court practices tending to uphold this approach (Roberts, p. 200). The International Court of Justice’s 2002 Judgment on the Merits in Case Concerning the Arrest Warrant of 11 April 2000 (Democratic Republic of the Congo v. Belgium) concluded that:

“the functions of a Minister for Foreign Affairs are such that, throughout the duration of his or her office, he or she when abroad enjoys full immunity from criminal jurisdiction and inviolability. That immunity and that inviolability protect the individual concerned against any act of authority of another State which would hinder him or her in the performance of his or her duties.”

para. 54

The Court examined State practice at the time, and held that it was:

“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 for Foreign Affairs, where they are suspected of having committed war crimes or crimes against humanity.”

(ibid., at para. 58)

The Court stressed that such immunities did not amount to impunity, since: (1) persons accused of war crimes could be tried in their own countries under relevant rules of domestic law; (2) the State they represent could waive immunity from foreign jurisdiction; (3) after the person ceases to hold office, foreign courts could try him or her for acts committed prior or subsequent to the period of office or acts committed in a private capacity; and (4) the person may still be subject to international criminal court proceedings where such courts have jurisdiction. (ibid., para. 61).

The creation of modern international criminal courts and tribunals took note of the International Court of Justice’s fourth exception against the immunity of Heads of States and their qualified political agents in the Arrest Warrant case. Unlike suits brought before domestic courts of another State, therefore, international criminal courts created by States explicitly contain advance waivers of such immunity for individual criminal prosecutions of Heads of State or Heads of Government. Article 27 of the Rome Statute of the International Criminal Court (ICC) explicitly provides that the official capacity of these persons:

“shall in no case exempt a person from criminal responsibility under this Statute, nor shall it, in and of itself, constitute a ground for reduction of sentence”,

and that

“immunities or special procedural rules which may attach to the official capacity of a person, whether under national or international law, shall not bar the Court from exercising jurisdiction over such a person.”

Similar provisions that maintain that the official position of the Head of State “shall not relieve such person of criminal responsibility nor mitigate punishment” are found in Article 6(2) of the Statute of the International Criminal Tribunal for Rwanda (ICTR), Article 7(2) of the Statute of the International Criminal Tribunal for the Former Yugoslavia (ICTY), and Article 6(2) of the Statute of the Special Court for Sierra Leone. 

In its 2004 Decision on Immunity from Jurisdiction in Prosecutor v. Charles Ghankay Taylor, the Special Court of Sierra Leone dismissed Liberian President Charles Taylor’s motion to quash the indictment. The Court affirmed that it was established by treaty to fulfill its international mandate as part of the machinery of international justice (paras. 38-41), and Article 6(2) of the Statute of the Special Court (which had identical counterparts in the Statutes of the ICTY and ICTR) encapsulated: 

“the principle…now established that the sovereign equality of states does not prevent a Head of State from being prosecuted before an international criminal tribunal or court…Article 6(2) of the Statute is not in conflict with any peremptory norm of general international law…the official position of the Applicant as an incumbent Head of State at the time when these criminal proceedings were initiated against him is not a bar to his prosecution by this court.”

(paras. 52-53)

In the ICC, Heads of State:

“enjoy immunity ratione personae only during their term of office…without prejudice to the application of the rules of international law concerning immunity ratione materiae.”

(Article 4 of the Rome Statute)

The Appeals Chamber in its 2019 Judgment in Prosecutor v. Omar Hassan Ahmad Al-Bashir held that: 

“there is neither State practice nor opinio juris that would support the existence of Head of State immunity under customary international law vis-à-vis an international court. To the contrary, such immunity has never been recognized in international law as a bar to the jurisdiction of an international court… No immunities under customary international law operate in such a situation to bar an international court in its exercise of its own jurisdiction… article 27(2) of the Statute is relevant not only to the adjudicatory jurisdiction of the Court, but also to the Court’s ‘enforcement jurisdiction’ vis-à-vis States Parties to the Rome Statute. States Parties to the Rome Statute have, by virtue of ratifying the Statute, accepted that Head of State immunity cannot prevent the Court from exercising jurisdiction – which is in line with customary international law. There is no reason why article 27(2) should be interpreted in a way that would allow a State Party to invoke Head of State immunity in the horizontal relationship if the Court were to ask for the arrest and surrender of the Head of State by making a request to that effect to another State Party. The law does not readily condone to be done through the back door something it forbids to be done through the front door. In such situations, the requested State Party is not proceeding to arrest the Head of State in order to prosecute him or her before the courts of the requested State Party: it is only lending assistance to the Court in its exercise of the Court’s jurisdiction.” 

(Key Findings of the Judgment, paras. 1 to 4)

The 2019 Al Bashir Judgment has invited extensive critical commentary from scholars, especially with challenges unique to the cooperation agreements of States Parties to the Rome Statute to implement the Court’s warrants of arrest to enable the Court to acquire ratione personae jurisdiction against Heads of State such as that issued in 2023 for Russian Federation President Vladimir Putin and the arrest warrant issued in 2024 for Israel Prime Minister Benjamin Netanyahu. The ICC has been relatively more successful getting its arrest warrants executed when Heads of State were no longer in office, as when the Ivory Coast transferred former President Laurent Gbagbo in 2011 (where he was acquitted 8 years later), when Sudan’s new government declared that it would turn over former President Omar Al-Bashir to the ICC in 2020 after the al-Bashir was overthrown in 2019 (but has not done so as of this writing), and when the Philippines’ new government availed of its treaty obligations under INTERPOL to hand over former President Rodrigo Duterte to the ICC in 2025.  

The non-cooperation or deficient cooperation of States Parties to the Rome Statute (such as in the case of Mongolia, and other State reactions against the ICC arrest warrant for Israeli Prime Minister Benjamin Netanyahu) in the implementation of arrest warrants of international criminal courts and tribunals against Heads of State, in my view, does not itself create decisive and authoritative State practices that countermand the explicit waivers States made against Head of State immunities for ratione materiae jurisdiction, as explicitly provided in treaties such as the Rome Statute, the Statute of the ICTY, the Statute of the ICTR, the Special Court of Sierra Leone, among others. At best, these instances of delayed, deficient, or failed cooperation introduce evidence of States Parties’ resort to Head of State immunities as a practical justification against immediate implementation or execution of the ICC’s arrest warrants and the Court’s acquisition of ratione personam jurisdiction over persons identified in its arrest warrants. As of this writing, however, these instances of non-cooperation fail to generate any de facto termination of treaty provisions that do not permit Head of State immunity as a shield against ratione materiae jurisdiction for international crimes.