A recent edition of the International Review of the Red Cross dedicated its content to examining a seemingly simple question: ‘How does international humanitarian law develop?’, touching upon the history of international humanitarian law (IHL), its current status and future prospects.

In this week’s episode of Humanity in War, podcast host Elizabeth Rushing unpacks these questions with Dr. Cordula Droege, ICRC’s Chief Legal Officer and Head of the Legal Division, and Dr. Eirini Giorgou, a legal adviser in the ICRC’s Arms and Conduct of Hostilities Unit specializing, among other topics, on explosive weapons in populated areas.

Cordula, let’s begin with you, and with a particularly ambitious question that will lay the foundation for our discussion. What, in your opinion, were some of the key milestones of the development of IHL and where have those brought us today?

Cordula:  Yes, thank you. So it is an ambitious question because, of course, development of the laws of war, humanitarian law, has existed since wars have existed because there’s always been rules to limit war, since time immemorial. But the history of modern international humanitarian law, I would say in a nutshell, can be told in five key milestones. And then perhaps a new area of treaty making.

The first would be the 1864 First Geneva Convention, which was about the protection of wounded soldiers in the battlefield. And the idea was that all combatants deserve to be treated with humanity and to receive medical care regardless of the side that they are on.

The second milestone would have been the 1907 Hague Peace Conferences, which were meant to be about building peace. But in the margins of them, if you will, or perhaps too much in the center of them, was also the question of regulating war. And so you have the Hague Regulations of 1907 that are still actually relevant today. They dealt with limiting the effects of war partly on civilians, partly also in occupied territory, partly on prisoners of war. Very limited rules still, but they were an important milestone at that time.

The third milestone is, of course, the First World War. And the important thing there was that, there were about eight to nine million prisoners of war in the First World War and the International Committee of the Red Cross visited these prisoners of war, saw their plight, saw that they needed to be in touch with their families, saw that they needed proper food, shelter, etc., and that there was no international law regulating this. And so, it proposed at the end of the war an international convention for the protection of prisoners of war. Already at that time, the ICRC also saw the plight of civilians, civilian villages destroyed, the deaths, the refugee flows, and tried to also get protection for civilians in armed conflict but didn’t achieve it at that time.

Then came the Second World War, with its toll of both military and civilian casualties and suffering. And after the Second World War in 1949, States came together and updated the first Geneva Conventions, which were two by then. So, it was the about the wounded and sick combatants in the field and at sea, but then also updated the Convention on Prisoners of War. Very importantly, and that was a big milestone, they also adopted a Fourth Geneva Convention on the Protection of Civilians in Times of War and adopted one article in all those Geneva Conventions to regulate civil war, which was something that had not been regulated, as it was seen as a matter of domestic law.

On the one hand, in the wake of the Spanish Civil War but also looking ahead to the wars that were already raging, in the 1940s there was a feeling that civil war should also be regulated. But it was, of course, very contained by States as well as the protection of civilians was contained by States because at that time, again, the ICRC also tried to have protection of civilians from what is called the ‘conduct of hostilities’, i.e. from fighting, from bombing, from the air, from destruction of their cities, etc.

But at that time, in 1949, States were not ready for this. They were not ready to limit themselves and rejected that. And so that led about 30 years later to the fifth milestone, which were the 1977 Additional Protocols to the Geneva Conventions, which on the one hand for the first time properly addressed what is called the conduct of hostilities, so, limiting military operations to protect civilians from their effects, but also adopted a second Additional Protocol to expand on the protection of people in non-international armed conflict situations, what is often called civil wars.

In this new area of treaty making in 1977, there were still many gaps were left. The ICRC and others at the time proposed that there should be a convention specific to weapons, which resulted in the Convention on Conventional Weapons of 1980 with Protocols. The idea was it was a framework convention that would allow States to add protocols as weapons developed to limit their effects and their use, or even to prohibit them. For instance, one of those protocols is a protocol that bans blinding laser weapons.

With that started really what we sometimes call the era of humanitarian disarmament, which was a shift away from seeing disarmament in the spirit of the nuclear weapons disarmament framework, as a framework of international security relations, to seeing weapons and disarmament through the lens of their effects on people. And so there you have the anti-personnel mine ban convention, what is often called the Ottawa Treaty. You have the banning of cluster munitions. You also have more recently a treaty that limits arms trade, including when there’s a risk of violations of human rights and humanitarian law, and the latest of those is the Treaty on the Prohibition of Nuclear Weapons, which was also the result of a humanitarian perspective on the effects of nuclear weapons and which entered into force in 2021.

I leave it at that. And that’s only the treaty part of the development of IHL and perhaps we can come back later on other ways in which IHL develops.

You read my mind, because that’s exactly where I would like to go with the conversation. As you rightly noted, a lot of what you were talking about since 1864 are legally binding treaties and conventions. So, if we’re looking at the present day and we are assessing the trends over the last few decades, we can see that there have been some non-binding norms that have become, in some instances, the preferred instrument for States to move forward in terms of the development of international humanitarian law. Can you speak to that briefly?

Cordula: Yes, and I would say three things at the outset, perhaps. The first thing I would say is you always have to have in mind the time that it takes to develop international humanitarian law. I just mentioned that, you know, since World War I, the ICRC tried to have international law protecting civilians. And it took a long time, almost 70 years, for this to be properly addressed in a treaty.

Second, while I gave you this outline of how IHL has developed through treaties, it develops in many different ways. One of the main ways is what we call customary international law, which is law that States accept as binding for themselves because they have expressed a legal opinion that it is binding and because they have a State practice in that respect. It’s influenced by many factors. It’s influenced by the jurisprudence of international and national tribunals. It’s influenced by State practice that we’ve just said, and it’s also influenced by these non-binding instruments, by academic work and so on that all become part of international humanitarian law and sometimes and in some instances and can also become seen as binding over time.

The typical example that is often given is, of course, the case law of the tribunal for the former Yugoslavia or non-international armed conflict, which fills many of the gaps that still existed in treaty law on non-international armed conflict, even basic things like the principles of distinction and proportionality and precautions, which weren’t really set out sufficiently and which are now accepted as being customary even in non-international armed conflict.

Another, perhaps a non-binding instrument to mention, is the San Remo Manual on Naval Warfare, which was also from 1994, and which was also a document that isn’t binding in itself, but – in the absence of very clear rules and or in the absence of updated rules – has often become the go-to document on the law of naval warfare.

That said, there are also standards that are non-binding and remain so for the time being. Examples of this, for instance, would be the Montreux Document on private military and security companies, which has a good practice part. And of course, the good practices were never meant to be binding law. They were meant to be good practices to implement the law. You have, for instance, the Paris Principles and Guidelines on children associated with armed forces or armed groups and the Paris Commitments to protect children from unlawful recruitment or use by armed forces or armed groups, which are also non-binding but have been used very much in armed conflict situations to guide the practice of States. You have the Safe Schools Declaration, which is a political commitment by States to protect schools from being used for military purposes, going a bit further than what the law actually requires in order to ensure safe education, and the Political Declaration on Explosive Weapons in Populated Areas that was recently adopted in June of last year is part of these political commitments that States make.

These can be very valuable because they are often documents that seek to give practical guidance and flesh out what the legal obligations are, or help States to implement the legal obligations or even go further, as I said, for the Safe Schools Declaration. So maybe not every practical measure is at a given time, an obligation, or required measure under an obligation, but it can be in certain times. Every single time, it’s about really fleshing out what the obligations can be or helping States to better implement their obligations and achieve better compliance for international humanitarian law in this case, or better protection of civilians.

Time to turn to you, Eirini, with this backdrop in mind. This trend over the last few decades of a general movement towards non-binding norms that become law has developed naturally alongside a second trend – a geopolitical environment wherein it’s increasingly challenging to come to concrete, multilateral agreements. That said, you were part of a major success story within this quite pessimistic environment, and that’s this Dublin Declaration on the use of explosive weapons in populated areas (EWIPA). Can you tell us about that agreement itself and describe the road to its success in terms of process and political maneuvering?

Eirini: Yes, indeed. As you said, the Declaration was a milestone with regard to both the substance and the process. Substantively, it’s the first instrument that commits States to restrict or refrain from the use of explosive weapons in populated areas where such use may cause civilian harm. And this, in itself, is groundbreaking. It’s not every day that States agree to self-restrict the use of force in armed conflict.

Cordula just described how long it has taken throughout the decades for IHL to develop when it comes to weapons restrictions, let alone when the restriction applies not just to one or two types of weapons, but a large category of weapons such as explosive weapons. The declaration was adopted so far by 83 States from almost every region of the world, including major military powers, which in itself, I would say, an astounding result. Of course, it’s a political instrument, so it’s not a treaty. It doesn’t aim to create new legal norms. It doesn’t aim to reinterpret the law. It aims to facilitate respect for IHL and to strengthen the protection of civilians through policy commitments and practical measures.

The road to this successful outcome was long. I had the privilege of being involved in this diplomatic process, which lasted almost three years from the moment it was formally launched. This is often the case in multilateral diplomacy. Things take time, and as you may imagine, this wasn’t an easy topic to begin with at all. Many States were reluctant to tie their hands and adopt restrictions and limitations on the use of weapons that really account for the largest part of their military arsenals. I must admit that when I started working on this file over five years ago, the outcome that we have now – a strong text with strong support by over 80 States – was really hard to envisage.

Looking back, I think there are a number of elements that contributed to the successful outcome and it’s really useful to do this exercise when we project into future processes that may take place regarding other areas of IHL. If I were to identify a couple of factors that led to the successful result, I would say the first one is the existence of a committed and determined group of likeminded actors – States, civil society organizations, international organizations, the ICRC of course, was in the middle of that, that were dedicated to this cause and were ready to champion, to keep the momentum, to push things forward, to keep the bar high throughout the negotiations.

Then the exemplary leadership of Ireland who was leading this process throughout these three years and who conducted an open and transparent and inclusive negotiation was also key, I think, especially in engaging some very influential States that were very skeptical towards this endeavor. Also, the informal nature of the negotiations, they were even dubbed consultations, even though they were practically negotiations. This also proved conducive to more flexibility among States and a higher degree of compromise.

The ICRC was following this process from the very beginning. We, I believe, really played a key role, not just contributing our humanitarian and legal expertise and our experience from our work in context of urban warfare, and the aftermath, but also in insisting on keeping a high bar in the commitments. We were throughout the process calling on States to commit to avoiding the use of heavy explosive weapons in populated areas. And where we landed was surprisingly quite close to that.

Maybe a last factor – as it happens, often external factors can be very influential in this type of processes. In this case, what we saw was the international armed conflict between Russia and Ukraine, which is a highly mediatized conflict, really brought the suffering of civilians under heavy bombing and shelling starkly to the attention of the international community, including States. I’d say this conflict was undoubtedly a push factor for many States to endorse the Declaration because they really saw the relevance. They saw the magnitude of the problem, which, of course, we and others have seen in many other parts of the world, from the Middle East to Afghanistan to Somalia and elsewhere.

So, I’d say there are definitely lessons learned from this process and the very successful outcome that would be worth replicating in other processes in the future.

Thank you, Eirini, for that recap and also for the hard work that you put in leading to the Dublin Declaration over the last three years. And congratulations again on being part of that massive accomplishment.

I won’t go so far as to say that you’ve just outlined a formula for success, but there are certainly some concrete lessons learned from that process. Cordula, let’s keep this clear success story of the Dublin Declaration in mind and the process of it that Eirini just outlined, and turn back to some of the other pressing issues of international humanitarian law in contemporary armed conflict. Can you see other areas or other fields of law that could benefit from some of the lessons learned of the Dublin process on explosive weapons in populated areas?

Cordula: Yes. And let me perhaps by way of introduction say something about how we think about development of the law and whether the law should be developed. I think what’s important here is to say that our starting point is always a humanitarian question or a humanitarian concern. Is there a humanitarian issue either that we see in our operations and that we feel needs to be addressed or that could manifest itself in the future? And if so, does existing international humanitarian law address this?

This can be directly and explicitly or it can be through the interpretation of existing law. If not, if there is a gap, that is the moment and only then when you start asking yourself whether the law should be developed. And by the way, the ICRC actually has, in the Statutes of the Red Cross Red Crescent Movement, a mandate to prepare for the development of international humanitarian law.

There’s an assumption there that international humanitarian law will always develop. It doesn’t stand still. Then you have to ask yourself the question about the feasibility and what can you do about it. Sometimes you might think, maybe we should clarify the law and be able to consolidate a bit how the law protects people from certain weapons, from certain behaviors, etc. Sometimes we might feel that stronger law is needed, but that it’s unlikely that we will be able to achieve it, or that we might even have a regression in the protection that we have an existing law. Then you also think are there are other pathways to pursue and that sometimes also when you think, maybe political commitments, good practices, these kinds of documents might actually advance the conversation short of developing the law.

Sometimes you might feel that the humanitarian risk is so serious that existing law is insufficient either because there clearly is a gap or there’s no prohibition, or there’s no limitation, or because States interpret the law in such unclear ways that it’s insufficiently protective. That was the case, for instance, for us with nuclear weapons. We felt that there is such an important humanitarian issue here that it requires a treaty prohibiting nuclear weapons. The entire Red Cross and Red Crescent movement was convinced and so that was what we worked towards.

Today, one of the areas where we feel that we need a new treaty to limit a new technological development is on autonomous weapons systems, where we feel that the law is too unclear to be sufficiently protective. Although it is, of course, protective and it already limits autonomous weapons systems, the law also doesn’t answer all the societal and ethical questions that these new technologies pose.

Thinking about such issues as, for instance, the autonomous weapons systems, I would say the EWIPA Declaration for me has several important lessons. I’ll perhaps mentioned three. One is that even short of a treaty, you can achieve a lot. When the process matters, when the political declaration can put an issue on the table, when a political declaration like the EWIPA Declaration basically reverses the burden of proof and sets in motion a process where armed forces and States need to account for how they are carrying out military operations – not accounting in a legal sense, of course, because, again, we’re in a political sphere – but account for what is happening in urban warfare, then that can be very, very valuable.

Second, I think what we learned from the EWIPA Declaration is you can have very strong and good language, and sometimes stronger than people might think is possible. It’s a question of working towards this, championing it, arguing, bringing the evidence about it in order to convince and influence.

Third, either for a treaty or a declaration, I think an important lesson is that they are only ever the starting point, and that then the work starts on creating wide support. The EWIPA declaration has 80 signatories, which is enormous, but of course, we want many more. We want it to be even stronger. So working towards wide support and then secondly, working towards implementation in practice.

And this is really where the rubber hits the road and when you really need to work very, very hard to keep the momentum, to have the practical discussions, at the level of the departments of defense or the level of the policies, at the level of training of the armed forces, etc. I think that’s also something that we need to keep in mind – you have the development of the law and then you always need to have in mind already the implementation of the law.

Back to you, Eirini, I have two last questions for you. First, we spoke a lot during this discussion about legally binding norms versus ‘soft law’, for lack of a better description. What really is the difference between law and policy when we are talking about minimizing the harmful effects of armed conflict in reality?

And then a second question, building on what Cordula just described, if we’re looking at implementing these newly developed norms and standards on explosive weapons in populated areas, what are these next steps to get the rubber to hit the road, to get States on board with the Dublin Declaration and bring its provisions to life?

Eirini: The difference between law and policy was a very hotly debated question. There was a lot of discussion during the negotiations on the EWIPA declaration on whether States should only commit to limit the use of explosive weapons where this was required by IHL – where this was a legal obligation already existing – or whether they should commit to further restrict the use of these weapons as a matter of policy, even in those cases where such use might be at first instance, lawful.

I would say in my mind, at least to some degree, this law versus policy dilemma was somewhat artificial in the context of the explosive weapons declaration. It ignored the simple fact that a policy commitment to avoid or restrict or refrain from the use of explosive weapons in populated areas will, in essence, facilitate respect for the law. This is because IHL will in many cases prohibit the use of heavy explosive weapons in populated areas if properly interpreted. Then some States argued that they will only use explosive weapons in populated areas in a lawful manner when allowed under IHL, but they failed to clarify how they interpret and implement the law when it comes to these weapons. To say that we will use these weapons in a lawful manner does not take us a very long way towards ensuring that civilians will be protected and the law will be respected when there is this lack of clarity.

Compliance with IHL is of critical importance and there’s no doubt about that and needs to be strengthened, especially when hostilities take place in challenging environments like urban or other populated areas. But the question here is what it means practically to strengthen compliance with IHL, and militaries often implement the law through policy, and this policy clarifies the meaning of legal obligations. It translates legal obligations into concrete, practical measures. Policy could be rules of engagement, could be tactical directives and other types of military doctrine. And this policy is, of course, binding for its recipients, commanders and armed forces, staff alike. There’s also plenty of cases where we see grave civilian harm occurring because of seemingly lawful attacks. This is in no way to underestimate the importance of the law, but rather to illustrate that the law is not always necessarily the only or the ultimate answer. And this is why I think that this law versus policy dilemma was artificial. And that one policy in this case actually helps to implement the other.

To come to your last question, the explosive weapons declaration obviously is not the end of our efforts. The main priorities, as Cordula said, are now its universalization and its full and effective implementation.

There are a few reasons why all States should endorse this Declaration whether or not they are directly involved in urban warfare. The first one is quite simple: the urbanization of warfare is a global phenomenon, but also the consequences of the urbanization of warfare are equally global. If you think about people displaced by armed conflict, often crossing borders, if you think about the ripple effects of the disruption of essential services due to bombing and shelling, such as the impact on food security, this goes beyond national borders. The effects of the use of heavy explosive weapons in populated areas really are not contained within the borders of the territory which is primarily impacted. The impacts ripple throughout the globe.

Second, all States have not only an interest in but also a duty to strengthen respect for IHL, and to strengthen the protection of civilians. And this is precisely what the Declaration aims to do.

And third, the declaration, what it really does is create an international standard of behavior. The more States endorse the Declaration, the stronger the standard will become, and the better the outcome for IHL compliance and of course, for the fate of civilians around the world.

When we look at implementation, the Declaration itself foresees a mechanism to monitor its implementation. The first meeting in the context of this mechanism will take place in 2024, in Oslo, but States are already beginning work on reviewing their existing policy and practice and adapting it, or at least identifying gaps and identifying what needs to change in order for them to meet the commitments they’ve undertaken under the political Declaration. Last year, we published a milestone report on explosive weapons in populated areas with detailed practical recommendations for political authorities and armed forces on measures they should take to implement what we call a policy of avoidance. These measures will allow them to avoid using heavy explosive weapons in populated areas. These recommendations can be very useful to States in implementing the political Declaration where they have committed to restrict or refrain from the use of explosive weapons in populated areas. We will also, as we have done for many years, now continue engaging bilaterally and confidentially in dialogue with States and their armed forces, to identify good practices to strengthen the protection of civilians in urban warfare from the use of explosive weapons, including ways and measures that will allow States to avoid the use of heavy explosive weapons in populated areas all together, which is what we have been calling for on States and non-State armed groups for over a decade, and what we continue to call on all parties to armed conflict to do.

See also

• Eirini Giorgou, Preventing and eradicating the deadly legacy of explosive remnants of war, February 23, 2023
• Nils Melzer & Elizabeth Rushing, Humanitarian neutrality in contemporary armed conflict: a conversation with Nils Melzer, January 26, 2023