Joint Blog Series: Application of International Humanitarian Law by Domestic Courts

Editor’s Note: This post is part of the joint series of posts hosted by EJIL:Talk!, Lawfare and Intercross (blog of the International Committee of the Red Cross) and arising out of the 3rd Transatlantic Workshop on International Law and Armed Conflict held in Oxford this summer.

It is well known that in an order such as international law where there is no universal, compulsory judicial system, domestic courts play an important role not only in enforcement, but also in interpretation and development of particular international legal rules. This is especially the case in international humanitarian law (IHL), an area that constantly faces existential critique for its lack of effective enforcement mechanisms. Moreover, it was only in the 1990s with the emergence of modern international criminal justice that many of the specific rules of IHL came to be interpreted and developed since their codification several decades before. Against this background, domestic courts are increasingly called on to apply and interpret IHL.

The purpose of this post is to offer a brief overview of the circumstances that might lead a domestic court to examine IHL, the extent to which such jurisprudence can be considered as contributing to the development of IHL, and some of the problems that arise here.

How does IHL come to arise before domestic courts?

There are a number of situations that might call for a domestic court to draw on IHL during the proceedings. In such cases, the court will either apply IHL directly (e.g. where a domestic law or government policy is being judicially reviewed for compliance with the international obligations of the State) or indirectly (e.g. where a domestic law or other international obligation of the State is being applied in a situation that requires a renvoi to IHL for content-determination, such as when interpreting a human right in the context of an armed conflict).

Examples of domestic courts directly applying IHL include the ongoing Serdar Mohammed litigation in UK courts. Indeed, this case is especially interesting as the first instance judge and the Court of Appeal faced claims by the Ministry of Defence and UK government that the latter had the right to detain under both treaty and customary law. At both levels this claim was rejected, but not before a very lengthy engagement by the judges with the interpretation and content of treaty and customary IHL. The Israeli Supreme Court similarly applied IHL in its Targeted Killings judgment, reviewing national policy in light of humanitarian law, human rights law and domestic law.

Alternatively, a domestic court may be called on not directly to apply IHL but to look to it in applying and interpreting other legal rules. In A and B v Israel, for example, the Israeli Supreme Court looked to the Fourth Geneva Convention rules on internment to interpret the 2002 Unlawful Combatants Law. Similarly, in the Guantanamo habeas litigation before the District of Columbia courts, the courts have, to varying degrees, drawn on the law of international armed conflict to ‘inform’ the detention authority considered to have been conferred on the President by Congress.

There are, of course, a number of limitations on the ability of domestic courts to engage with IHL. First, depending on the jurisdiction and the source of law relied on for invoking IHL (treaty or custom), a particular State might take a more or less dualist approach to the incorporation of international law into the domestic legal system. Second, a domestic court might be restricted by international law rules (e.g. jurisdictional immunities) or domestic law rules (e.g. act of state or the political question doctrine).

Domestic courts ‘developing’ IHL?

Having considered a few examples of the circumstances that might call for domestic courts to look to IHL, it must next be asked what impact this domestic jurisprudence can have on IHL. |For example, can domestic courts develop IHL, or are any normative consequences confined to the domestic legal system of which the court is a part? It is clear that domestic courts are often called upon to apply or interpret IHL generally, such that their conclusions are, in theory, not confined to a domestic law point but should apply to all States party to the particular treaty (or indeed all States where the content of customary international law is the issue). Thus, in the A and B v Israel case, noted above as an example of indirect application, the Supreme Court offered its view of certain general controversies in IHL. For example, the Court held that Article 42 of the Fourth Geneva Convention does not permit any form of status-based detention; rather, an individual threat determination is always required. This was then used to interpret the scope of detention authority under the 2002 law. In Serdar Mohammed, where the UK courts were called on directly to apply a purported right under IHL, the judges had first to determine whether such a right existed under either treaty or customary-based humanitarian law. In determining that the right did not exist, it offered a clear view of the state of existing international law in this area, and, if it is correct, such an interpretation would apply as much to Syria as it does to the UK in Afghanistan. Similarly, the UK’s Divisional Court in Al-Jedda, when faced with the question of what is required under the vague language in Article 78 of the Fourth Geneva Convention (requiring civilian internment decisions to be made according to a regular procedure and subject to review), took the view that the more detailed requirements under Article 43 applied.

These cases are examples of a domestic court offering its view of the current lex lata. In this sense, such domestic jurisprudence might constitute a subsidiary means for the determination of rules of law in the sense of Article 38(1)(d) of the ICJ Statute. The persuasiveness of any interpretation will, of course, depend on the rigour of the court’s analysis and its adherence to traditional methods of law creation and interpretation in international law. In Serdar Mohammed, for example, both the first instance judge and the Court of Appeal considered the Ministry of Defence’s claims against the traditional test for custom, concluding that practice and opinio iuris offered very little support for the government’s contention. The contentious nature of these issues, however, means that domestic courts are also having a more direct normative impact, concretising or even developing the law. Thus, domestic jurisprudence can itself constitute State practice for the purpose of either contributing to the development of custom or interpreting treaty obligations. Where the domestic court takes the position it does due to its own view of the content of customary international law, then that judgment will also potentially constitute a valuable source of the State’s opinio iuris. Serdar Mohammed is a good example of all of these various ways in which domestic jurisprudence might impact IHL.

Limits on the value of domestic court jurisprudence

It remains to be considered what factors might exist that limit the value of domestic jurisprudence in interpreting or developing IHL. One point that has arisen in the Serdar Mohammed case is the possible existence of contrary practice or opinio iuris from other branches of the State.  The issue also arose in the Targeted Killings case. In that case, the Israeli Supreme Court held, contrary to the position of the Israeli government, that the loss of protection by civilians against direct attack only applies “for such time” as they take a direct part in hostilities is a rule of customary international law, in addition to being contained in Article 51(3) of Additional Protocol 1 (1977) . This disagreement between two branches of government could undermine the weight one should give to the practice and opinio iuris both of the court and the other branch in any custom calculation. Of course, where the particular court is at the top of the domestic judicial hierarchy, the other branches of the State may have little discretion left to continue with their dissident stance. A second and more basic point has also been alluded to, that is, the rigour with which the domestic court interprets and applies IHL. Put simply, it may well be that the court gets the law wrong (see Yael Ronen’s discussion of the US Agent Orange case as a good example). Nonetheless, should other domestic courts and States generally follow suit, that incorrect interpretation of the law may well later become the correct interpretation.

A final caveat that must be kept in mind when considering the impact of domestic jurisprudence on IHL is the fact that often the court’s analysis will address IHL simultaneously with other areas of law, such as domestic law and human rights law. In such cases, it may be difficult to draw out general points about IHL alone. The Israeli Targeted Killings case and its ‘least restrictive means’ test for lethal targeting is a good example here. Though offering considerably greater protection than the ordinary IHL standards, according to which combatants and civilians directly participating in hostilities can be targeted without consideration of actual necessity, the influence that domestic and human rights law had on the court’s approach makes it difficult to draw general conclusions about the current state of IHL here (that is not to say, however, that its conclusions on this point were necessarily inaccurate when considering the ways humanitarian and human rights law might work together).