It is apparent that the international community benefits from the International Court of Justice (ICJ)’s role in developing and clarifying key principles of international law, which can also help settle future disputes. The Court, in the Northern Cameroons case (Cameroon v. United Kingdom), contends that its rulings must actually affect the parties involved in the dispute before it, emphasizing that the “[c]ourt’s judgment must have some practical consequence” (p. 34). By acknowledging the significance of the aforementioned role, a possible way the Court could ensure that its rulings have “practical consequence” would be to develop international law by making third-state obligations clear under Common Article 1 (CA1) of the four Geneva Conventions of 1949 and by taking into account the subsequent state practice on that provision.

This article will address three aspects: the external dimension of CA1, the development of the subsequent practice for its implementation, and the States’ obligations in the event that CA1 is breached. These three aspects are connected to one another in some way. States must take positive actions in order to comply with CA1’s external dimension. States’ practice forms subsequent practice, and third States are obliged to act in accordance with the Jus Cogens norms.

Common Article 1 and its external dimension

In Alleged Breaches of Certain International Obligations in respect of the Occupied Palestinian Territory (Nicaragua v. Germany), [hereinafter referred to as the “Occupied Palestinian Territory case”], German legal counsel states that “the obligation to ensure respect embodied in common Article 1 can do no more than suggest that all States must conduct a proper risk assessment” (p. 38, para 27). The German legal counsel also acknowledges the positive obligation contained in CA1 by stating that “Germany only supplies arms on the basis of detailed scrutiny, a scrutiny that not only respects, but far exceeds the requirements of international law” (p. 12, para 24). Indeed, the Lex Lata suggests exactly the reverse. In accordance with CA1, the duty to ensure respect consists of both positive and negative obligations.

The 2016 ICRC Commentary clarifies that:

“153  The obligation to ensure respect also has an external dimension related to ensuring respect for the Conventions by others that are Party to a conflict. Accordingly, States, whether neutral, allied or enemy, must do everything reasonably in their power to ensure respect for the Conventions by others that are Party to a conflict.

170  The fact that common Article 1 is part of an international treaty, however, means that it is not a loose pledge but a commitment vested with legal force. This was affirmed by the International Court of Justice in the Nicaragua case where the Court considered that the clause reflected a legal obligation.[94] The term ‘undertake’ used in common Article 1 also underlines the High Contracting Parties’ commitment to ensure respect by others. In its ordinary meaning to ‘undertake’ means to ‘formally guarantee, pledge or promise’.[95]” [emphasis added]

In Application of the Convention on the Prevention and Punishment of the Crime of Genocide (Bosnia and Herzegovina v. Serbia and Montenegro), the ICJ held that:

“It is not merely hortatory or purposive. The undertaking is unqualified …; and is not to be read merely as an introduction to later express references to [other obligations].” Merits, Judgment, 2007, para. 162).

In the wall advisory opinion, the ICJ confirmed the existence of an external dimension of CA1 by indicating that:

 “follows from that provision that every State party to that Convention, whether or not it is a party to a specific conflict, is under an obligation to ensure that the requirements of the instruments in question are complied with” (Wall advisory opinion, para. 158).

We believe the Court developed and presented a correct interpretation of CA1 that under the law of State responsibility (Article 48 of ARSIWA), it is meant to impose obligations on third States with regard to the action of that State that is not a party to the ‘specific conflict’.

Subsequent practice in relation to the implementation of the CA1

Although we believe that a treaty shall be interpreted in good faith in accordance with the general principles of interpretation (Articles 31 and 32 of the VCLT), the ICJ employed the subsequent practice of the parties as a means of interpretation in the Nuclear Weapons Advisory Opinion (para. 19.). The ILC Draft of 1966 provided in its Article 38 that “a treaty may be modified by subsequent practice.” (YBILC 1966 II, 236 f).

The International Committee of the Red Cross (ICRC) states, that  “common Article 1 does not add anything new to what is already provided for by general international law” (2020 ICRC, Commentary toGC III, para. 177). As a matter of fact, nothing new needs to be added to international law. The Court just needs to take international organizations’ resolutions into account as a subsequent practice.

Pursuant to CA1, High Contracting Parties are obligated to fulfill specific negative obligations, and they are prohibited from supporting, promoting, or assisting parties to a conflict in violating the Conventions. In this regard, the UN Security Council, in Resolution 681 “Calls upon the High Contracting Parties to the said Convention to ensure respect by Israel, the occupying Power, for its obligations under the Convention in accordance with article 1 thereof” (para 5). Additionally, the Human Rights Council passed a landmark resolution on 26 March 2024, calling on  “all States to cease the sale, transfer and diversion of arms, munitions and other military equipment to Israel, the occupying Power, in order to prevent further violations of international humanitarian law and violations and abuses of human rights” (para. 13).  The  EU Council  also confirmed this interpretation:

“Common Article 1 of the Geneva Conventions is generally interpreted as conferring a responsibility on third party states not involved in an armed conflict to not encourage a party to an armed conflict to violate international humanitarian law, nor to take action that would assist in such violations, and to take appropriate steps to cause such violations to cease.”

Yaser Salarian is a lawyer and legal expert renowned for his insights into international law, particularly in the areas of sanctions, international humanitarian law, and disarmament. With a master’s degree from the School of International Relations, Salarian’s academic foundation is as solid as his professional reputation. His notable works include articles delving into the interpretation of Security Council resolutions and the jurisprudence of the International Court of Justice. Beyond his scholarly pursuits, Salarian is involved in providing international law consultations and fostering scientific cooperation with institutions.

Hamed Esmaeilpour is a lawyer, legal researcher, and university lecturer specializing in international law, stands at the forefront of human rights advocacy. Hamed Esmaeilpour holds a doctorate degree from Allameh Tabataba’i University and his expertise shines through in his book, “The right to liberty and security of person in the European Court of Human Rights jurisprudence”. Outside the realm of academia, Esmaeilpour is committed to providing international law consultations and fostering scientific partnerships with institutions.

Read more about this and related topics in the Asian Journal of International Law.