The ICC and the ICJ are both based in The Hague and both carry “international court” in their names, but they do completely different jobs. The International Court of Justice settles legal disputes between countries. The International Criminal Court prosecutes individual people for the world’s gravest crimes. One deals with state responsibility; the other with personal criminal guilt. That single contrast drives almost every other difference between them.
States vs. Individuals: The Core Difference
The ICJ hears cases brought by one country against another. Only sovereign states can be parties. An individual, a company, or a nongovernmental organization cannot file a claim at the ICJ or be named as a defendant there. When the ICJ rules that a country violated international law, the obligation falls on the country as a whole, not on any official who made the decision.
The ICC works the opposite way. Its defendants are natural persons facing criminal charges. A former president, a military commander, or a militia leader stands trial as an individual, and a conviction produces a personal criminal sentence. The ICC cannot hold a nation liable, order a government to pay damages, or declare that a state violated a treaty. So when news coverage says “the international court charged someone with war crimes,” that almost always means the ICC.
What Each Court Hears
The ICJ handles questions of public international law. Typical disputes involve maritime boundaries, treaty interpretation, and whether one state’s conduct breaches its obligations to another. Recent proceedings have included South Africa’s allegations of genocide against Israel in the Gaza Strip and Nicaragua’s claim that Germany facilitated genocide by continuing arms transfers. These cases turn on state responsibility, not whether any particular person is criminally guilty.
The ICJ also issues advisory opinions when the UN General Assembly, the Security Council, or other authorized UN organs and specialized agencies request them.1INTERNATIONAL COURT OF JUSTICE. Charter of the United Nations Advisory opinions are generally not binding, and the requesting body decides what effect to give them.2INTERNATIONAL COURT OF JUSTICE. Advisory Jurisdiction They still carry significant legal and moral weight.
The ICC’s subject matter is narrower and criminal. It can prosecute four categories of offense: genocide, crimes against humanity, war crimes, and the crime of aggression. Aggression was added through amendments adopted at a review conference in Kampala in 2010 and covers the planning or execution of an armed attack by one state against another that clearly violates the UN Charter. Only individuals in a position to direct a state’s political or military actions can be charged with aggression. The other three categories reach a wider range of defendants.
The ICC also operates on the principle of complementarity. It does not replace national courts; it steps in only when a country is genuinely unwilling or unable to investigate and prosecute the crimes itself.3UN Meetings Coverage and Press Releases. Rome Statute of International Criminal Court to Come Into Force It is a court of last resort.
How Each Court Gets a Case
Every UN member state is automatically a party to the ICJ Statute.4United Nations. Chapter XIV – The International Court of Justice, Articles 92-96 But being a party to the Statute does not mean the court can hear any case involving that country. Jurisdiction in contentious cases requires consent. A state can give consent by accepting the court’s compulsory jurisdiction through a declaration under Article 36(2) of the Statute, by agreeing to jurisdiction inside a specific treaty, or by consenting case by case through a special agreement.
Because consent is required, a country can simply refuse to participate, and the court has no mechanism to compel appearance. The United States withdrew its acceptance of compulsory jurisdiction in 1985 after the ICJ ruled against it in the Nicaragua case.5UNTC. Charter of the United Nations and Statute of the International Court of Justice
The ICC’s jurisdictional reach is built differently. As of early 2025, 125 countries are parties to the Rome Statute. The court can exercise jurisdiction when a crime was committed on the territory of a state party, when the accused is a national of a state party, or when the UN Security Council refers a situation. The ICC Prosecutor can also open an investigation on their own initiative, but doing so requires authorization from a pre-trial chamber.
Security Council referrals matter because they can pull in countries that never joined the Rome Statute. The referrals regarding Darfur (Sudan) and Libya both involved non-member states. On the other hand, several major powers, including the United States, China, Russia, and India, are not Rome Statute parties, which limits the ICC’s practical reach involving their nationals or territory absent a Security Council referral.
What Each Court Can Impose
The outcomes look nothing alike because the two courts operate in different branches of law. An ICJ judgment typically declares that a state violated international law, orders it to stop the unlawful conduct, or awards reparations from one state to another. The ICJ cannot fine or imprison anyone.
The ICC sentences individuals. The maximum penalty is 30 years of imprisonment, or life when the extreme gravity of the crime and the circumstances of the convicted person justify it. The court cannot impose the death penalty. It can also order fines and forfeiture of proceeds from the crime.
The ICC has a reparations system that has no ICJ equivalent. After a conviction, the court can order reparations funded by assets collected from the convicted person and, when those are insufficient, supplemented by voluntary contributions through the Trust Fund for Victims.6The Trust Fund for Victims. Reparation Implementation Reparations can be individual or collective and may include medical treatment, psychological rehabilitation, vocational training, and memorialization projects. Victims can also participate in ICC proceedings through legal representatives. The ICJ has nothing comparable, because states, not individuals, are the parties there.
Enforcement Problems at Both Courts
Neither court has its own police force, and enforcement is the weak point for both.
When a state loses at the ICJ and refuses to comply, the winning state can take the matter to the UN Security Council under Article 94 of the Charter. The Security Council “may, if it deems necessary, make recommendations or decide upon measures to be taken to give effect to the judgment.”7Codification Division Publications. Chapter XIV – Article 94, Charter of the United Nations In practice this is rarely used, and any permanent member can veto enforcement action. That makes ICJ judgments effectively unenforceable against the five permanent members or their close allies.
The ICC relies on member states to arrest and surrender suspects. Part IX of the Rome Statute obliges all states parties to cooperate fully with the court, including executing arrest warrants regardless of the suspect’s official status. Article 27 is explicit that head-of-state immunity does not bar ICC jurisdiction. Compliance has been uneven. The long-outstanding warrant against former Sudanese President Omar al-Bashir went unexecuted for years as he traveled to countries nominally obligated to arrest him. Enforcement ultimately depends on the political will of individual governments.
Membership and the UN
The ICJ is structurally part of the United Nations. The UN Charter lists it as one of the organization’s six principal organs, alongside the General Assembly, the Security Council, the Economic and Social Council, the Trusteeship Council, and the Secretariat.1INTERNATIONAL COURT OF JUSTICE. Charter of the United Nations Its budget comes from the UN’s regular budget, funded by assessments on all member states. All 193 UN member states are automatically parties to the ICJ Statute.
The ICC is not part of the UN. It is a standalone international organization created by the Rome Statute, a multilateral treaty adopted in 1998 that entered into force on July 1, 2002.8UN Treaty Collection. Rome Statute of the International Criminal Court It has its own international legal personality and is funded by its 125 states parties through the Assembly of States Parties. The UN and the ICC have a cooperation agreement that allows information sharing and permits the Security Council to refer situations to the ICC Prosecutor. That referral power is the most visible intersection between the two institutions and has been used twice so far.
One boundary worth flagging: the United States is a party to the ICJ Statute as a UN member but terminated its acceptance of compulsory ICJ jurisdiction in 1985, and it is not a party to the Rome Statute. Congress passed legislation declaring that the United States is not bound by the Rome Statute and will not recognize ICC jurisdiction over American nationals.9Office of the Law Revision Counsel. 22 USC 7421 – Findings So neither court has broad authority over the U.S. absent specific consent or a Security Council referral.
Side-by-Side Summary
- Established: The ICJ was created in 1945 by the UN Charter. The ICC was created by the Rome Statute, which entered into force in 2002.10INTERNATIONAL COURT OF JUSTICE. The Court
- Who appears before the court: ICJ hears disputes between sovereign states only. ICC prosecutes individual people.
- Subject matter: ICJ addresses public international law, including treaty interpretation and state obligations. ICC handles genocide, crimes against humanity, war crimes, and the crime of aggression.
- Membership: All 193 UN member states are automatically parties to the ICJ Statute. The ICC has 125 states parties that voluntarily ratified the Rome Statute.
- UN relationship: ICJ is a principal organ of the United Nations, funded by the UN budget. ICC is legally independent, funded by its own member states.
- Penalties: ICJ orders state-level remedies like reparations or declarations of wrongful conduct. ICC sentences individuals to prison terms of up to 30 years or life.
- Enforcement: ICJ judgments can be referred to the Security Council under Article 94. ICC arrest warrants depend on member state cooperation.