Why was the International Court of Justice (ICJ) established? How is it structured, and what is the significance of having judges from different countries on the bench? How are they appointed, and what qualifications do they need to possess?
The ICJ was established after World War II to advance the goal of getting countries to use laws and institutions to resolve their disputes instead of resorting to hostility and conflict. It is the world’s highest-profile international tribunal: an organ of the United Nations created to adjudicate disputes between nations and provide advisory opinions on issues arising under international law. Created as the successor to the League of Nations’ Permanent Court of International Justice, it operates in accordance with the UN Charter and a separate ICJ Statute. Every member of the UN is a party to the ICJ Statute. The court can only hear cases against states, rather than individuals. The latter is the responsibility of domestic courts, as well as other international courts, including the International Criminal Court (ICC).
Nations may bring disputes before the ICJ when their direct interests are affected. And since a 2019 preliminary ruling in a case The Gambia brought against Myanmar, the court has also recognized a new form of standing: “erga omnes partes standing,” or standing based on obligations “in relation to everyone,” or owed to all. This allows a state party to a treaty that protects common legal rights to enforce those rights even if that state is not specially affected by the violation.
Decisions on the merits often take years, but parties can request, and the ICJ sometimes grants, “provisional measures” requiring countries to desist from certain activities while a case winds its way toward a decision on the merits.
Though especially prominent given its role as the legal organ of the UN, the ICJ is one of several tribunals with distinct functions. Among these are the ICC, the Permanent Court of Arbitration, and the International Tribunal for the Law of the Sea.
Fifteen judges serve on the ICJ, though there can be additional ad hoc judges appointed, as in the case by South Africa against Israel. The members of the court are elected by the UN General Assembly and the UN Security Council and serve for nine years. They must be of “high moral character” and possess the qualifications required in their respective countries for appointment to the highest judicial office or have expertise in international law. ICJ judges must have different nationalities, and the court as a whole is supposed to include expertise from different legal systems around the world.
Why do states submit their cases for adjudication to the ICJ? Are there other legal avenues available for nations or other parties that want to hold countries accountable for behavior that allegedly violates international law?
Countries naturally strategize about how to advance their particular interests and concerns when deciding whether to bring a case to the ICJ. To begin with, the case has to be one where there is a reasonable likelihood the court will find it has jurisdiction. Not every dispute can be submitted to the ICJ. The court gains jurisdiction through consent of the parties—either through submission of the dispute to the court or because the parties have agreed to jurisdiction in advance, often through a treaty that provides that the ICJ has jurisdiction to resolve disputes under that treaty. (Unlike U.S. courts, the ICJ can also issue advisory opinions in certain situations, particularly if requested to do so by the Security Council or the General Assembly.) A country is likely to bring a case to the ICJ when its leadership believes there is a reasonable possibility the tribunal will rule in the country’s favor and when bringing a case before the tribunal will generate favorable attention on an issue of concern for the country. Separately or in conjunction with an ICJ case, a country could pursue a diplomatic strategy to advance its concerns, impose economic sanctions, or seek relief in another tribunal, such as the Permanent Court of Arbitration.
Does South Africa v. Israel have repercussions for international law? How so?
The definition of the crime of genocide is demanding because it requires a specific intent to destroy a group. This case may further elaborate how tribunals apply this definition and distinguish the crime of genocide from other potential violations of international law, including war crimes over which the ICJ lacks jurisdiction.
In two cases—The Gambia’s case against Myanmar over its alleged acts of genocide against the Rohingya in violation of the Genocide Convention and the Netherlands’ and Canada’s case against Syria for its alleged violation of the Convention Against Torture—the ICJ found that countries could bring cases even when they had only a generalized interest in enforcing an obligation under the treaties that all states owe to one another and did not otherwise have a direct interest in the dispute. South Africa is proceeding on a similar rationale. The ICJ’s decision to grant South Africa’s application for provisional measures only serves to strengthen this basis for standing and could greatly increase the role of the court in similar cases in the future. That will draw the ICJ into more contentious political debates, but it also offers, if the court is prudent, the possibility of bringing legal analysis to highly charged disputes.
Does this case have the potential to alter the ICJ’s standing in the international view?
Because tribunals exist in an unforgiving and difficult political environment, even the principled ones often have little choice but to consider the practical aspects of their potential decisions. They aim to issue a judgment that will be regarded as legitimate by contending parties. They aim to be understood by experts, journalists, and the larger public. And they consider how to contend with the risks of rendering a judgment or issuing an order that might be ignored.
Indeed, in rendering its decision in the South Africa v. Israel case, the ICJ made specific reference to the obligation of the parties to abide by the decisions of the court precisely to respond to this concern. It is difficult for a tribunal to maintain its legitimacy if its orders are regularly ignored. This reality constitutes one of the inherent dilemmas of international tribunals that lack any enforcement capacity. (ICJ decisions are formally subject to enforcement by the Security Council, but each of the five permanent members can veto any effort at enforcement.) At the same time, international tribunals tend to be made up of judges from different countries, cultures, and legal systems. Bridging the resulting divides takes time and compromise.
Both of these realities—the importance considering how decisions will be enforced and the divides judges must bridge internally—can cause tribunals to proceed with some caution when it comes to the merits of politically thorny cases. Their deliberations often stretch over many years. When their ultimate decisions are finally issued, the results can sometimes read like an imperfect attempt to reconcile inherent contradictions.
A case in point is the ICJ’s decision on the legality of the threat or use of nuclear weapons by states. Judges would have been hard-pressed to imagine a world where countries would have given up their nuclear deterrent simply because an ICJ ruling told them it was unlawful to hold on to such weapons. Yet by design, powerful nuclear weapons wreak the kind of indiscriminate destruction of civilian life that seems almost impossible to reconcile with international humanitarian law. The resulting decision reads as being on the verge of being at war with itself: the threat or use of nuclear weapons ordinarily runs counter to the laws of war, but that may not prevent their use where the survival of a state is at stake. Such use, nonetheless, must be consistent with the UN Charter and the laws of war, and countries are under a broad imperative to advance nuclear disarmament.
Decisions of the ICJ can, nonetheless, carry important weight—shifting the understanding of those around the world about the legality or illegality of the actions taken by the states involved. And even if the decisions are not formally enforced by the Security Council, they are often enforced in a more decentralized way, by shaping the way in which states respond to the parties involved in the dispute. For example, the ICJ’s decision that Russia’s invasion of Ukraine was unlawful likely played a role in many states’ willingness to provide unprecedented financial and military support to Ukraine in its defense against Russia. International law often has force in this way—by shaping how states respond to one another’s actions. Hence, law can sometimes influence even those states determined to ignore it.
How does the Carnegie Endowment for International Peace’s work relate to the ICJ?
During its early history, Carnegie sought to increase the role and importance of international tribunals as a means of preventing international conflict. Indeed, the institution was created in part to support the further development of international tribunals that could channel conflict between countries into neutral tribunals that could render judgments that would be widely viewed as legitimate.
History belies the idea that international tribunals steeped in legal doctrine are enough to banish war. But history also shows that Andrew Carnegie was not entirely wrong to recognize that the world could benefit from international tribunals, which is why he funded construction of the majestic Peace Palace for the Permanent Court of Arbitration—an institution that was planned and supported in no small measure by the Carnegie Endowment for International Peace. That grand building is now the home of the ICJ. Today, these and a number of other international tribunals face a version of the dilemma that just about any court must navigate in a domestic or international environment: how to fulfill their interpretive missions while enhancing their legitimacy and preserving their capacity to carry out their assigned functions.
Carnegie also figures in the history of the legal concept of genocide, which Raphael Lemkin helped develop through seminal writings while he worked at Carnegie in the aftermath of World War II and the Holocaust, which is memorialized on January 27. Much of the public understands that the concept of “genocide” refers to the commission of a heinous atrocity. What they may be less clear about is that the crime of genocide has a precise definition in international law that establishes a high threshold to prove the offense has been committed.
It is worth bearing in mind that even when they are at their best, international tribunals can have limited contributions—yet those contributions can be meaningful and carry a power of their own. They can succeed in channeling into institutions and legal argument political disputes about borders, economic statecraft, natural resources, or military tactics. Yes, they are poorly suited to compensating individuals who have lived through harrowing circumstances or to healing painful divides rendered worse by brutal attacks. And it is true that the challenges that lie ahead as a result of the Hamas attack and Israel’s subsequent response in Gaza to that attack are beyond the capacity of any tribunal to repair. Yet when international tribunals take a careful and prudent path—bearing in mind differing, reasonable arguments and contending views—they can help chart a path forward even in the midst of the worst horrors.
Mariano‑Florentino (Tino) Cuéllar is the president of the Carnegie Endowment for International Peace. A former California Supreme Court justice and executive branch official in two presidential administrations, he was also the Stanley Morrison Professor at Stanford Law School, where he taught international criminal law.
Oona A. Hathaway is a nonresident scholar in the Global Order and Institutions Program at the Carnegie Endowment for Peace. She is the Gerard C. and Bernice Latrobe Smith Professor of International Law at Yale Law School and director of the Yale Law School Center for Global Legal Challenges.