Symposium on Ljubljana – The Hague Convention on Mutual Legal Assistance: Critical Reflections – A New Tool in the Fight Against Impunity for Core International Crimes

[Vaios Koutroulis is a Professor of Public International Law at the Faculty of Law and Criminology, Université libre de Bruxelles]

Vaios Koutroulis was a member of the Belgian delegation participating in the negotiations of the Convention and acted as the coordinator of working group 1 at the Ljubljana conference, where the Convention was negotiated and adopted. The views in this post are expressed in the author’s personal capacity. 

On the occasion of the publication of the 2023 edition of the Universal Jurisdiction Annual Review, aside from the “multiplication of national investigations into international crimes in Ukraine” (p. 10), Trial international notes more generally the “increasing use of the principles of universal and extraterritorial jurisdiction to curb impunity for international crimes” (see here). But, how can a State prosecute efficiently persons accused of war crimes, crimes against humanity or other serious international crimes in cases when the relevant conduct took place in the territory of one State, (some of) the victims and witnesses have found refuge in the territory of another, and the author is present in the territory of yet another State? How can the prosecuting authorities of a State have access to the evidence and witnesses necessary to successfully prosecute such a case? And, as the case may be, how can it be made sure that the persons allegedly responsible for such crimes will not definitively avoid facing any criminal proceedings by residing in the territory of a third State? These were essentially the concerns that seeks to address the new Ljubljana-The Hague Convention on International Cooperation in the Investigation and Prosecution of the Crime of Genocide, Crimes against Humanity, War Crimes and other International Crimes. 

Introductory Remarks

After a long process lead by Argentina, Belgium, Mongolia, the Netherlands, Senegal, and Slovenia, involving many consultations, a diplomatic conference was held in Ljubljana from 15 to 26 May 2023, which led to the adoption of the Convention on 26 May 2023. The Convention shall be open to all States for signature in 2024 (more information on the process are available here).

The Convention is particularly long and, aside from the preamble, is composed of eight parts: part I on general provisions, part II on central authorities and communication, part III on mutual legal assistance, part IV on extradition, part V on the transfer of sentenced persons, part VI on victims, witnesses, experts and other persons, part VII on institutional arrangements and part IX with the final provisions of the Convention. This post will focus on some of the general provisions of the Convention and discuss namely its scope as well as the provisions relating to jurisdiction. 

Material Scope of Application of the Convention 

The Convention takes its cue from the Rome Statute with respect to its scope of application. Indeed, from the early steps of the consultations’ process, the participating States had agreed that the crimes listed in articles 6 (genocide), 7 (crimes against humanity) and 8 (war crimes) of the Rome Statute, as these crimes were adopted in 1998, represented the lowest common denominator in terms of international crimes, and would serve as the point of reference for the material scope of application of the Convention. 

When articles 2 and 6 are examined jointly, the Convention’s material scope of application can be seen schematically as composed of three concentric circles. 

In the first, middle circle—at the heart of the Convention—lie the crime of genocide, crimes against humanity and war crimes as they were adopted in Rome in 1998, whose definitions are set out in article 5. As per article 2(1), these crimes will be covered by the Convention automatically upon its entry into force with respect to the States concerned. 

The Convention also has a number of annexes with eight additional crimes: the new war crimes that have so far been adopted by amendments to the Rome Statute in 2010, 2017 and 2019 (annexes A to E), torture (annex F), enforced disappearance (annex G), and the crime of aggression as it was defined in Kampala (annex H). According to article 2(2), the Convention only applies to these crimes when the States involved in the criminal cooperation (the requesting and the requested) have accepted this application with respect to the relevant annex. In that sense, the crimes listed in the annexes can be viewed as part of a second, broader circle of material application of the Convention. States may choose whether they want the Convention to cover the crimes listed in the annexes or not but, when they do make the relevant notification, the application of the Convention is mandatory. 

On the contrary, article 6 of the Convention gives the opportunity to States to decide on an ad hoc basis whether they want to use the Convention for a specific request of international cooperation on criminal matters, provided that the conditions set out in the article are met. This allows for the broadest possible use of the Convention, in line with the objective of facilitating international cooperation in criminal matters and strengthening the fight against impunity (see article 1 and preamble). However, in such cases the application of the Convention is purely optional—as the title of article 6 itself suggests—and depends on the consent of the States concerned. This optional application forms the third, external circle of the Convention’s scope of application.

The Definitions of Crimes

There was general agreement that the definitions of crimes were not going to be open to negotiation and this was the position followed both during the consultations process and throughout the negotiations. 

This is reflected in the text of the Convention adopted in Ljubljana with two notable exceptions. The first one is the decision not to include in the list of war crimes applicable in international armed conflicts the crime listed in article 8(2)(b)(xx) of the Rome Statute, that is the act of 

“Employing weapons, projectiles and material and methods of warfare which are of a nature to cause superfluous injury or unnecessary suffering or which are inherently indiscriminate in violation of the international law of armed conflicts, provided that such weapons, projectiles and material and methods of warfare are the subject of a comprehensive prohibition and are included in an annex to this Statute, by an amendment in accordance with the relevant provisions set forth in articles 121 and 123”.

As it is obvious from the text, the weapons, projectiles and other methods of warfare coming under the scope of this crime must be specified by amendment. Since no relevant amendment has yet been adopted, the provision remains an empty shell and this is what prompted its deletion from the relevant list of war crimes in the Ljubljana-The Hague Convention (cf article 5(4)(b)). In any case, when such an amendment will be adopted in the context of the Rome Statute, the crime can also be added as a separate annex to the Convention. 

The second exception concerns the definition of “gender” in the context of crimes against humanity, set out in article 7(3) of the Rome Statute: 

“For the purposes of this Statute, it is understood that the term “gender” refers to the two sexes, male and female, within the context of society. The term “gender” does not indicate any meaning different from the above.”

This provision was deleted from the definition of crimes against humanity already at the early stages of the consultations and was not included in any of the early draft versions of the Convention (see here, here and here). This deletion was further supported by the fact that the International Law Commission had made the same choice in its 2019 Draft articles on prevention and punishment of crimes against humanity (draft article 2) for reasons clearly explained in the commentary to this draft article (paragraphs 41 and 41). 

Establishing Jurisdiction on Core International Crimes

The issue of jurisdiction proved to be one of the most contentious of the Convention and concerns were even raised publicly during the negotiations by some of the NGOs that were present (see here and here). 

It should be said from the outset that the negotiations were guided by the general recognition of the need not to undermine existing or developing international obligations. This is explicitly asserted in article 3 of the Convention, entitled “General principle of interpretation” which stipulates that 

“Nothing in this Convention shall be interpreted as limiting or prejudicing in any way existing or developing rules of international law, including the definitions of the crimes to which this Convention applies.”

The main provisions relating to the exercise of jurisdiction are articles 8 (“Jurisdiction”) and 14 (“Aut dedere, aut judicare”). The first sets down, among others, the obligation for States to establish the universal jurisdiction of their courts over the crimes to which the Convention applies in case a suspect is present in a territory under their jurisdiction (paragraph 3 of article 8). The second provides that a State has the obligation to “submit the case to its competent authorities for the purposes of prosecution”, or, alternatively, to extradite the suspect or to surrender him or her to a competent international tribunal (paragraph 1 of article 14). 

Looking into the equivalent articles in the Convention against torture, the International Court of Justice, in its 2012 judgment in the case concerning Questions relating to the obligation to prosecute or extradite (Belgium v. Senegal), acknowledged that these obligations are intertwined and serve the common purpose of “enabling proceedings to be brought against the suspect, in the absence of his extradition, and to achieve the object and purpose of the Convention, which is to make more effective the struggle against torture by avoiding impunity for the perpetrators of such acts” (para. 74). Indeed, the Court correctly asserted that the obligations to criminalize, to give courts universal jurisdiction in the relevant cases, to make a preliminary inquiry into the facts and, unless the suspect is extradited, to submit the case to the competent authorities for the purposes of prosecution, “taken as a whole, may be regarded as elements of a single conventional mechanism aimed at preventing suspects from escaping the consequences of their criminal responsibility, if proven” (para. 91). 

The big majority of States that participated in the negotiations recognized that this “mechanism” applied to all the crimes covered by the Ljubljana-The Hague Convention and therefore had no difficulty with reproducing in the Convention the text of the articles from the Convention against torture. However, a very limited number of States felt that it was not certain that the relevant obligations applied to the same extent to all the crimes covered by the Convention and its annexes. The problem invoked more specifically related to the obligation to establish universal jurisdiction for all the relevant crimes in cases where the suspect is present only for a very short period of time in the territory under the jurisdiction of a State party to the Convention. In the interest of adopting the Convention by consensus and of allowing for its broadest possible ratification—for example possibly by States which are not parties to some of the conventions or amendments from which the crimes in the annexes are drawn—a compromise was reached in the form of allowing for a reservation to the obligation to establish universal jurisdiction set down in article 8(3) of the Convention. The relevant provision is article 92(3) and states that

“A State may, at the time of signature, ratification, acceptance or approval of or accession to this Convention, formulate a reservation, for renewable periods of three years, based on grounds existing in its domestic law and in accordance with its obligations under international law, limiting the establishment of its jurisdiction under article 8, paragraph 3.”

Although the text of the provision refers generally to “the establishment of its jurisdiction under article 8, paragraph 3”, when read in light of the discussions held during the negotiations, the reservation may concern the kind of presence that will be necessary in order to trigger the exercise of universal jurisdiction. It may not, for example, establish additional conditions for the exercise of universal jurisdiction, nor may it limit the scope of such jurisdiction only to national territory thereby excluding other territories that may be under the jurisdiction of the state, such as territories under military occupation. Nor is it possible of course to use article 92(3) in order to completely exclude the exercise of universal jurisdiction, as it is obvious from the text of the provision itself which refers to a reservation “limiting the establishment of jurisdiction” not ruling it out altogether. The need for the reservation to be in accordance with existing obligations of States under international law was meant as an additional guarantee ensuring that the potential reservation has as limited a scope as possible. The requirement to renew the reservation every three years, and thus to re-examine both its conformity with international law and its usefulness, is further testimony to the reluctance with which States approached the possibility to accept a reservation on article 8 (3). 

Concluding Remarks

Although the scope of the Convention and its general provisions may attract attention from public international law scholars, it is likely the “technical” provisions of the Convention that will prove more valuable in everyday practice. It is the provisions on joint investigation teams, on cross-border observations, on the confiscation of assets, on the procedure for executing requests for mutual legal assistance, for extradition, or for the transfer of persons that are the living and breathing heart of the Convention. Every practitioner that was consulted during the whole process that led to the adoption of the Convention stressed how important having an instrument like this would be for international criminal cooperation. The States negotiating in Ljubljana put all their efforts in arriving at a satisfactory final text. Once the Convention is open for signature in 2024, it will be up to all the States to ratify it and thus provide their prosecuting authorities with the necessary tools to fight impunity efficiently.