This is the ILOAC-Team overarching research project. It is conducted under the supervision of Prof. van Steenberghe as his main project as a FNRS Research Associate. The research intends to examine the interaction between the different branches of international law applicable in armed conflict and to determine whether those branches may amount together to a coherent legal regime in the international legal order.

In this respect, it is understood, first of all, that the branches of international law concerned include, in addition to international humanitarian law, certain branches also applicable in peacetime, in particular human rights law, international criminal law, refugee law and international environmental law; secondly, that the coherence of the said regime is envisaged on the basis of an enriched conception of normative coherence developed in legal theory; finally, that the notion of normative regime refers to that of a ‘special’ legal system of international law including specific norms, both primary and secondary.

This objective will be pursued in three stages, namely, first, to theorize the ‘horizontal’ relationships reflected in contemporary practice between international humanitarian law and other relevant branches of international law; second, to propose, on this basis, the ‘vertical’ construction of an international law of armed conflict, making it possible to formulate solutions to concrete questions raised by the recent practice of armed conflict; and third, to identify the specific secondary rules of this ‘special’ normative regime.

See notably:

• the video by R. van Steenberghe on that project;   
• the paper by R. van Steenberghe, ‘La cohérence et le droit international des conflits armés comme système juridique’, CeDIE research paper, UCLouvain (2016);
• the edited volume by R. van Steenberghe, Droit international humanitaire: un régime spécial de droit international? (Brussels, Bruylant, 2013) 352 pp.;
• the publications below in relation to research projects entitled ‘the interplay between jus ad bellum and jus in bello’; ‘the interplay between international humanitarian law and international human rights law’; ‘the interplay between international humanitarian law and international environmental law’, and ‘the interplay between international humanitarian law and counterterrorism legislation’. 

1. Proportionality under jus ad bellum and jus in bello

Specific research has been carried out on the interplay between proportionality under jus ad bellum and proportionality under jus in bello. While identifying overlaps between the two kinds of proportionality, the research emphasizes the fundamental differences between them.

See notably:

• the paper by R. van Steenberghe, ‘Proportionality under Jus ad Bellum and Jus in Bello: Clarifying their Relationships’, Israel Law Review (2012) 107-124;

2. The principle of equality between belligerents in non-international armed conflict

The principle of equality of belligerents is considered an essential principle of international humanitarian law (IHL) because of its role for the respect of this law. It involves an equality of application of IHL between all parties to a conflict, irrespective of the lawfulness of their recourse to the use of force under jus ad bellum. Albeit initially conceived for situations of international armed conflict (IAC), it constitutes nowadays a dogma for the whole set of IHL rules, including those governing non-international armed conflicts (NIAC). It is however only by ‘analogy’ that it has been considered as applicable to such conflicts. Yet, these conflicts feature some major specificities. It is therefore required to question this application ‘by analogy’ and examine different aspects of the principle of equality of belligerents in NIAC. The research therefore questions the definition of such a principle in NIAC. It then identifies its legal bases and effects in such conflicts. Some developments also concern the impact of the principle on human rights law and domestic law.

See notably:

• Topic of the Ph.D. thesis of Philippe Jacques

1. A coherency-based approach to the interplay between international humanitarian law and human rights law

The interplay between international humanitarian law and human rights has been abundantly discussed in legal scholarship in the past. New developments, such the updated ICRC commentary of the Geneva Conventions and some judgements of the International Criminal Court, put that issue again on the front. The research proposes an approach to the interplay between the two bodies of law, which seeks coherence between them. Such approach starts from formal tools, such as the lex specialis principle or the principle of systemic integration, but it argues that substantial considerations are needed to guide the operation of those tools. The research proposes to resort to the legal theories on the notion of coherence of legal systems to provide guidance on such considerations.

See notably in relation to that coherency-based approach:

• paper by R. van Steenberghe, ‘The Impacts of Human Rights Law on the Regulation of Armed Conflicts: A Coherency-Based Approach to Dealing with Both the “Interpretation” and “Application” Processes’, International Review of the Red Cross (2022) 1345–1396.

2. Detention in non-international armed conflicts

The detention of persons in the context of armed conflicts is certainly one of the most common acts in such situations of violence. It must also be noted that the legal regime for such detention is still not clearly established today. It is therefore tempting to look for the anchoring of a legal basis, a ground for detention and the possibility of extending the protection of detained persons in the provisions of Article 3 common to the four Geneva Conventions (GC) and the Second Additional Protocol (APII), although these are very laconic in this respect. This anchoring is also sought in the interaction between the rules of international humanitarian law (IHL) and those of international human rights law (IHRL), although the latter are only binding upon states.

To address these gaps and limitations in the rules applicable to detention in non-international armed conflicts, this research has three objectives. First, to demonstrate that the detention of persons participating in hostilities in NIAC is consistent with IHL when carried out for security reasons and for the criminal offences related to the armed conflict. Secondly, as the notion of ‘security reason’ is vague and imprecise, this needs to be corrected by guidelines for detention by armed groups. And as far as state actors are concerned, the vagueness of the ground for detention needs to be corrected by IHRL. Third, as the regime of procedural safeguards in IHL is dictated by the ground of detention, given the non-existence of immunity from prosecution in the NACs, the judicial safeguards enshrined in Articles 3CG and 6 APII, even though originally designed to apply to criminal situations - alluding to the more detailed provisions of Article 6 AP II - must be extended to any form of detention in NIAC.

See notably:

• paper by P. Chambu Ntizmire, ‘La détention dans les conflits armés non internationaux : fondement juridique et garanties procédurales’, Annales de Droit de Louvain (2017) 255–274;
• monography by P. Chambu Ntizmire, La détention dans les conflits arlés non internationaux. Base légale, motif et garanties procédurales (Limal, Anthemis, 2022).

3. The European Court of Human Rights and international humanitarian law

Like other regional human rights body, the European Court of Human Rights has been led to pronounce on violations of those rights in situations of armed conflict. Although initially reluctant to refer to international humanitarian law, it gave due weight to that law in the Hassan case in 2014. Recently, however, it came back to a stricter position regarding the applicability of the European Convention on Human Rights to armed conflict in case of situations of active hostilities.

See notably:

• paper by R. van Steenberghe, ‘L’arrêt de la Cour européenne des droits de l’homme dans l’affaire Géorgie contre Russie (II): les limites de la Cour comme organe de contrôle du droit international humanitaire’, Annuaire français de droit international (2021) 263-303.

1. The interplay between international humanitarian law and international environmental law

It is well known that armed conflicts may cause serious damage to the environment. Many studies and works have addressed the issue of the protection of the environment in armed conflict. However, they often do it from the perspective of international humanitarian law. The proposed research intends to further protect the environment by resorting to another branch of international law: international environmental law. This raises the particular issue of the interplay between that branch of international law and international humanitarian law. This has been quite neglected in legal literature, especially by comparison with scholarship on the relationships between human rights and international humanitarian law.

The research intends to provide a theoretical framework for such interplay. This framework is mainly based on two processes, the interpretation process, through which international humanitarian law is interpreted in light of international environmental law, and the application process, whereby international environmental law applies alongside international humanitarian law.  However, these two processes must be guided by substantial considerations in order to seek coherence between international humanitarian law and international environmental law.

The research also intends to test the framework based on normative coherence  to different aspects of the environment, including biodiversity, hazardous substances, fresh water and the sea.

See notably:

• the symposium by J. de Hemptinne and R. van Steenberghe, ‘The protection of the environment during warfare: An International Environmental Law Perspective’, Journal of International Criminal Justice (2023) 1119-1298;
• the paper by R. van Steenberghe,  ‘International environmental law as a means for enhancing the protection of the environment in warfare: A critical assessment of scholarly theoretical frameworks’,  International Review of the Red Cross (2023) 1568–1599;
• the paper by R. van Steenberghe, ‘Interplay between International Environmental Law and International Humanitarian Law. Towards a Comprehensive Framework for Better Protecting the Environment in Armed Conflict’, Journal of International Criminal Justice (2023) 1123–1154;
• the paper by J. de Hemptinne, ‘Increasing the safeguarding of protected areas threatened by warfare through international environmental law’, International Review of the Red Cross, 2023, pp. 1393-1411.

2. Specific issues in relation to the protection of the environment in armed conflict

The ILOAC Team also makes research on specific issues related to the protection of the environment during warfare, including the crime of ecocide, the liability of business entities and the protection of animals in armed conflict.

See notably:

• the edited volume by J. de Hemptinne (with A. Peters and R.Kolb), Animals in the International Law of Armed Conflict (Cambridge, Cambridge Universiy Press, 2022);
• with Anne Peters, ‘Animals in war: At a vanishing point of international law’, International Review of the Red Cross (2022) 1-30;
• ‘Quelques réflexions au sujet de la définition du crime d’écocide et de ses rapports avec la Cour pénale internationale’, Journal des tribunaux (2021) 800-804;
• The post by J. de Hemptinne (with A. Peters), ‘A Plea for “Animalizing” the International Law of Armed Conflict’, Articles of War, Articles of War, 11 October 2022;
• The post by J. de Hemptinne, ‘Ecocide: an Ambiguous Crime?’, EJIL Talk!, 29 August 2022;
• The paper by Ezéchiel Amani (with Benjamin Traôré), ‘Environmental Obligations of Business Entities in Armed Conflicts’, International Review of the Red Cross (forthcoming, 2023).

The Democratic Republic of Congo (DRC) is subject to several armed conflicts, where international crimes are committed. Some of those crimes have been prosecuted by national Congolese courts. The research intends to examine that case law from a threefold perspective: descriptive, critical and prospective. Two projects are planned: updating the digest of case law published by Avocats Sans Frontièrest hrough the work done by students in the framework of the Rosa Park Clinic and writing an volume edited by lawyers from both the DRC and Belgium.  

See notably:

• the paper by E. Amani (with Pacifique Muhindo), ‘Prosecuting Rape as a War Crime in the Democratic Republic of the Congo: Challenges and Lessons learned from Military Tribunals’, The Military Law and the Law of War Review (2021) 44-54;
• the study by J. Mbokani, La jurisprudence congolaise relative aux crimes de droit international (2016-2018) (Kinshasa, Ed. Club des amis du droit du Congo, 2018) 200 pp.;
• the study by J. Mbokani, La jurisprudence congolaise reative aux crimes de droit international, Open Society Foundations, Johannesburg/New York (2016) 404 pp.;
• the paper by J. Mbokani, ‘L’activité des tribunaux congolais relative à l’application directe du Statut de la Cour pénale internationale: vers une banalisation des crimes de droit international?’, Revue de droit international et de droit comparé (2014) 113 et seq.

Since the inception of international humanitarian law (IHL), States, International Criminal Tribunals, the International Committee of the Red Cross and experts have often used analogies to determine and develop the scope of application of this law or the substance of its norms. Interestingly, the use of this analogical method expanded tremendously in the last decade.

On the one hand, the realities of warfare are evolving faster than ever and IHL actors invoke analogical arguments to build an adequate legal framework for new technologies (autonomous weapons systems, cyberwarfare, etc.), which are not – as such – regulated by this branch of International Law.

On the other hand, armed conflicts against organized armed groups are multiplying and IHL actors favor analogies to improve the relevant framework applicable to such conflicts, which is less developed than the one applicable to armed conflicts between States.

Despite a widespread and sometimes problematic use of analogies in IHL, legal scholarship does not offer a systematic and comprehensive assessment. Therefore, this project will examine how analogies contributed and still contributes to IHL development. In particular, the use of analogies in IHL raises four questions. First, this project will establish whether analogical arguments can be (legally) used under IHL (‘can we compare?’). Second, it will analyse the sources of IHL analogies (‘what to compare?’) and explore what this analysis shows about the main features of International Law and about the relationships between its branches. Third, this project will study the functions of IHL analogies (‘why comparing?’). Last, it will determine the limits for the validity and effectiveness of IHL analogies (‘at what conditions to compare?’).

See notably:

• the paper by P. Lesaffre, ‘Participation in a Non-International Armed Conflict: A Failed Analogy with Co-belligerency', Boston University International Law Journal (2023) 259-300.

From Afghanistan to Syria, from Mali to Yemen, cross-border armed conflicts involving one or more organized armed groups were breaking news headlines a couple of years ago and are still increasing in frequency. Although pre-dating this millennium, this recent form of armed conflict is unprecedented in both scale and impact. Consequently, this new type of hostilities challenges existing international humanitarian law (IHL), which originates from a period when cross-border armed conflicts were a rarity and not in the forefront of the international community’s consciousness.

Principally, this project determines whether cross-border armed conflicts require continuity, change, or transformation to existing IHL. Answering this research question, the project focuses on rules relating to IHL scope of application, more specifically, rules defining its scope ratione materiae (i.e. the rules relating to the classification of armed conflicts – ‘the what?’) and ratione personae (i.e. the rules guiding the identification of actors being belligerent parties to armed conflicts – ‘the who?’). The project has two parts.

The first part of the project concerns the classification of cross-border armed conflicts. It examines whether the current taxonomy of armed conflicts sufficiently captures this new type of hostilities. In particular, it analyses whether cross-border armed conflicts can be classified as non-international armed conflicts, even in cases of non-consented interventions by a State or an international organization.

The second part of the project addresses the issue of foreign participation in a pre-existing internal armed conflict, which is one aspect of IHL personal applicability to cross-border armed conflicts. By scrutinizing the law of non-international armed conflicts, the project finds a gap: this law does not offer a legal framework to regulate foreign participation in a pre-existing internal armed conflict. In a constructive approach, the project follows an analogical reasoning and suggests a solution de lege ferenda to fill this gap.

Through these developments, the project argues that cross-border armed conflicts need IHL to both maintain its continuity and change. In some respects, IHL adequately governs these conflicts, but in other respects, it must evolve.

See notably:

• the monography by P. Lesaffre, Le droit international humanitaire à l’épreuve des conflits armés transfrontières - Champs d’application matériel et personnel (Paris, Pedone, forthcoming 2024);
• the paper by P. Lesaffre, ‘Participation in a Non-International Armed Conflict: A Failed Analogy with Co-belligerency', Boston University International Law Journal (2023) 259-300;
• the paper by P. Lesaffre, ‘Double Classification of Non-Consented State Interventions: Magic Protection or Pandora’s Box?’, International Law Studies (2022) 408-452;
• the post by P. Lesaffre, ‘Classification of Non-Consensual State Interventions against an OAG’, Articles of ar, 11 August 2022;
• the contribution by Pauline Lesaffre, ‘Military Support and IHL: A Critical View of the Fragmented Approach’, in Who is Who on the Battlefield? The Actors Engaged in Contemporary Armed Conflicts, Proceedings of the Bruges Colloquium (2022) 94-103;
• the paper by P. Lesaffre and R. van Steenberghe, ‘The ICRC’s ‘support-based approach’: A Suitable but Incomplete Theory’, Questions of International Law (2019) 5-23.

The fragmentation of the scope of application of international humanitarian law into various categories of armed conflict - international and non-international, high-intensity and low-intensity - is not easily reconciled with the nature of contemporary hostilities. Hostilities are difficult to categorize once and for all. Indeed, nowadays, few armed conflicts are permanently international or non-international, high or low intensity. Whether Afghan, Central African, Congolese, Iraqi, Israeli-Palestinian, Ivorian, Libyan, Malian, Somali, Syrian, Ukrainian or Yemeni, these conflicts all evolve as they unfold, as external armed forces intervene and withdraw, the control these forces exert, and then lose, over other forces, the structuring and destructuring of armed groups in combat, variations in the intensity of military operations, and the loss and regaining of effectiveness by belligerents.

The aim of this research is precisely to analyze the contours of these mutation processes and their repercussions on applicable law. It is also to show that, in most of today’s armed conflicts, when these processes combine or follow one another, the system of classification of armed conflicts envisaged by international humanitarian law becomes increasingly obsolete and needs to be rethought.

See notably:

• the monography by J. de Hemptinne, Les conflits armés en mutation (Paris, Pedone, 2019), 358 pp.;
• the contribution by J. de Hemptinne, ‘Réflexions autour de la nature juridique des conflits armés en Afrique’, in Colloque de Rennes (Paris, Pedone, to be published (2024));
• the contribution by J. de Hemptinne, ‘Quelques réflexions sur les conflits de qualification et de régime juridique en droit international humanitaire’, in O. de Frouville and S. Touzé (eds), 70 ans après l’adoption des Conventions de Genève: Le droit international humanitaire confronté à de nouveaux défis ? Réflexions sur les interactions normatives (Paris, Pedone, 2022) 37-53;
• the post by J. de Hemptinne, ‘Classifying the Conflict in Gaza under International Humanitarian Law, a Complicated Matter’, EJIL:Talk!, 13 November 2023.

T

he research project focuses on international law applicable to naval mines and naval mine warfare (minelaying, mine hunting/sweeping). To date, only the Hague Convention (VIII) on the laying of automatic submarine contact mines (1907) deals specifically with this matter. However, naval mines and naval mine warfare have gone through some significant changes and evolutions since the beginning of the XXth century. A number of questions therefore arise, including the applicability of the Hague Convention (VIII) to modern naval mines, but also the applicability of other bodies of laws such as customary international law and international humanitarian law. A fresh look to these questions seems particularly relevant given the persistent use of naval mines in armed conflict (Black Sea, Red Sea, etc.), their highly disruptive effect in a world of deeply interconnected economies where sea lines of communication and freedom of navigation have perhaps never been more important, as well as the profound technological developments that naval mine warfare is undergoing these days (e.g. mine counter measure operations using surface and underwater drones).

• This is the topic of François-Xavier Decleyre’s Ph.D. thesis.

This Ph.D. research project analyses how territorial conflicts may affect the applicability of the conventional sources of international investment obligations, and the identification of the entities responsible for their creation and implementation. Focusing on situations of non-international armed conflicts, occupation, annexation, and de facto regimes, this work addresses legal issues that lie at the intersection between different fields of international law (including IHL), delineating concrete approaches that seek to inform the conduct of the main stakeholders concerned and the settlement of investor-state disputes.

• This is the topic of Erik Brouwer’s Ph.D. thesis.

1. The armed conflict between Ukraine and Russia

The research intends to examine various aspects of the armed conflict in Ukraine in light of international law, including military assistance to Ukraine, prosecution of international crimes and food safety.

See notably:

• the paper by P. Lesaffre, ‘L’alimentation comme arme de guerre de la Russie en Ukraine: réflexion sur la protection de la sécurité alimentaire par le droit des conflits armés’, Revue québécoise de droit international (2023) 117-153;
• the post by P. Lesaffre, ‘A Path Forward for Food Security in Armed Conflict’, Articles of War, 22 March 2023;  
• the podcast by R. van Steenberghe, ‘La guerre en Ukraine sous l’angle du droit international’, Journal des tribunaux, November 2022;
• the paper by R. van Steenberghe, - ‘La guerre en Ukraine sous l’angle du droit international. Mise en contexte et présentation du numéro spécial’, Journal des tribunaux (2022) 709-711;
• the paper by P. Lesaffre and R. van Steenberghe, ‘La poursuite des crimes internationaux commis en Ukraine: une mobilisation internationale inédite’ Journal des tribunaux (2022) 751-761
• the paper by J. de Hemptinne and R. van Steenberghe, ‘L'assistance militaire à l'Ukraine: sa légalité en droit international et la participation de ses auteurs au conflit contre la Russie’, Journal des tribunaux (2022) 727-736.

2. The armed conflict between the Hamas and Israel

See notably:

• the post by J. de Hemptinne, ‘Classifying the Gaza Conflict Under International Humanitarian Law, a Complicated Matter’, EJIL Talk!, 13 November 2023;
• the post by R. van Steenberghe, ‘A plea for a right of Israel to self-defence in order to limit the Israeli military operations. When jus ad bellum comes to the aid of jus in bello’, EJIL Talk!, 16 November 2023.

Since the beginning of the 21st century, there has been an increasing number of cases in which non-state armed groups occupy territory in the context of non-international armed conflicts (NIAC). Given security concerns and the needs for work, livelihoods and education, some non-state groups have succeeded in establishing well-developed systems of public governance and seek to manage the lives of millions of people living in areas under their control around the world as de facto quasi-state authorities, providing them with services of public nature.

However, there is no rule of IHL explicitly designed to regulate the relationship between a NSAG and the people living in the territories under its control. Wishing to avoid legitimizing armed groups and rebellions, states opposed the idea of a law of occupation applicable to armed groups in NIACs. The aim of the research is to fill this legal vacuum in order to subject NSAGs occupying territories to a specific regime of international law as well as to ensure the best possible protection of the people administered, living or located in the occupied territory.