Why International Courts? Understanding the Imperative for Global Justice Mechanisms

When a government turns on its own people – ordering massacres, enabling ethnic cleansing, or simply refusing to prosecute its own soldiers for war crimes – where does a victim turn? The answer, painstakingly built over the last century, is the international court. The growth of international criminal courts is not an accident of legal evolution. It is a deliberate response to a set of hard, recurring realities: that states sometimes fail their people, that the nature of armed conflict has changed, and that some crimes are too grave to be treated as anyone’s internal affair. Understanding why these courts exist is essential to understanding how international law actually works today.

The foundational problem: when states cannot or will not act 🔗

Every legal system is built on an assumption – that the state will enforce the law. National courts prosecute criminals, national armies are expected to follow rules, and national governments are expected to hold violators accountable. But this assumption collapses in two critical scenarios: when the state is directly responsible for the atrocities, or when it simply lacks the will and capacity to prosecute them.

This was the defining reality after World War II. The Nazi regime did not merely fail to prevent genocide – it was the perpetrator. There was no German court that could have meaningfully tried Hitler’s officials while the regime was in power. The establishment of the Nuremberg and Tokyo Tribunals marked a pivotal moment in the development of international criminal law, prosecuting major war criminals and setting important legal precedents. These tribunals were created precisely because no domestic system could deliver justice – and because the crimes committed were so enormous that the international community recognized it had both a right and a responsibility to act.

This logic became foundational. The ICC is intended to complement, not to replace, national criminal systems; it prosecutes cases only when states are unwilling or unable to do so genuinely. The principle of complementarity – as this is formally known – is not just a procedural rule. It is a direct acknowledgment of the problem that motivated the creation of international courts in the first place: that domestic accountability is often the first casualty of large-scale atrocities.

The shift from interstate wars to internal conflicts 🔗

Traditional international law was built for a world of wars between states – armies crossing borders, soldiers in uniforms, governments signing surrenders. That world never disappeared, but it became less representative of how actual violence unfolds. In the past fifty years more than 250 conflicts have erupted around the world; more than 86 million civilians, mostly women and children, have died; and over 170 million people were stripped of their rights, their property and their dignity. The overwhelming majority of these were not interstate wars but civil wars, ethnic conflicts, and insurgencies – all technically “internal” matters.

This shift created a serious legal gap. For much of the 20th century, international humanitarian law applied primarily to conflicts between states. Non-international armed conflicts – civil wars, insurgencies – were largely outside its reach. The legal framework had to catch up with reality. In the past fifty years, the most serious violations of human rights have occurred not in international conflicts but within states. Therefore, the Rome Statute incorporates contemporary international humanitarian law standards that criminalize, as war crimes, serious violations committed in internal armed conflicts.

The Yugoslav wars of the 1990s made this urgency impossible to ignore. The ICTY’s landmark Tadić decision provided much-needed clarity by defining armed conflicts and extending certain international armed conflict rules to non-international armed conflicts. This was a watershed moment – it established that the protections of international law were not switched off the moment a conflict was declared “internal.” The horrors of Srebrenica and Kigali could not be addressed by saying they were someone’s internal affair.

The growing recognition of individual rights under international law 🔗

Alongside the structural failures of states, there was a deeper conceptual shift underway in international law – a move away from a purely state-centric framework toward one that recognized individuals as bearers of rights and obligations. For centuries, international law governed relations between states. Individuals were largely invisible: victims had no standing, and perpetrators could hide behind sovereign immunity or the act of state doctrine.

The Nuremberg trials broke this paradigm decisively. The Charter of the International Military Tribunal and the subsequent Nuremberg trials revolutionized international law by applying its prohibitions directly to individuals – in this case the defeated leaders of Nazi Germany – thus effectively inventing international criminal law. The principle established was unambiguous: individuals, including heads of state and senior officials, could be held personally criminally responsible for international crimes. Official position was no longer a shield.

This development required institutional infrastructure to give it teeth. A legal principle without a court to apply it is largely theoretical. Since World War II, the international community has progressively developed a system of international jurisdictions to complement the jurisdictions of domestic courts, to try people accused of genocide, war crimes, and crimes against humanity. The Genocide Convention of 1948 and the Geneva Conventions of 1949 codified the crimes; the courts that followed were built to prosecute them.

The inadequacy of ad hoc mechanisms 🔗

After Nuremberg and Tokyo, international criminal law went into a long dormancy. After the war crimes trials which followed the Second World War, there was very little in the way of jurisprudence from national courts and almost none from international courts and tribunals until the ICTY and ICTR began their work in the 1990s. The Cold War froze international cooperation, and neither superpower had an interest in creating legal mechanisms that might one day be turned against them or their allies.

When the Cold War ended and new atrocities erupted in Yugoslavia and Rwanda, the international community scrambled to respond. The UN Security Council established the International Criminal Tribunal for the Former Yugoslavia (ICTY) in 1993 and, after the genocide in Rwanda, the International Criminal Tribunal for Rwanda (ICTR) in 1994. These were important developments, but they also revealed a fundamental weakness in the ad hoc approach. Each tribunal was created after the fact, for a specific crisis, with a limited mandate. They were expensive, slow, and geographically constrained. Justice was reactive rather than preventive.

The United Nations has emphasized the need for an international criminal court for multiple reasons: to achieve justice for all, to end impunity, to help end conflicts, to remedy the deficiencies of ad hoc tribunals, to take over when national criminal justice institutions are unwilling or unable to act, and to deter future war criminals. The push for a permanent court was therefore partly a reaction to the limitations of what had been built before.

The Rome Statute and the architecture of a permanent court 🔗

The culmination of these pressures was the Rome Statute of 1998, which established the International Criminal Court. On July 17, 1998, the Rome Statute was adopted in a vote of 120 in favor, 21 abstaining, and 7 opposed; the ICC was established as a permanent institution, entering into force on July 1, 2002. The Rome Statute is notable not just for creating a court but for articulating a clear rationale for why one was needed.

The Preamble of the Rome Statute speaks of crimes that “shock the conscience of humanity” and affirms that “the most serious crimes of concern to the international community as a whole must not go unpunished.” The Rome Statute emphasizes that the ICC shall be a permanent institution with jurisdiction over the most serious crimes of concern to the international community as a whole, and shall be complementary to national criminal jurisdictions. The four categories of crimes under its jurisdiction – genocide, crimes against humanity, war crimes, and the crime of aggression – represent the international community’s codified answer to the question of what is too serious to leave to national discretion alone.

Today, the Hague-based ICC seeks to investigate and prosecute those responsible for grave offenses such as genocide, crimes against humanity, and war crimes, with 125 member countries as parties. Cases have ranged from civil wars in the Democratic Republic of Congo and Uganda to the conflict in Darfur, Venezuela, and the Russia-Ukraine war – all situations where domestic accountability either failed or was structurally impossible.

Deterrence, victims’ justice, and the maintenance of peace 🔗

The purpose of international courts is not merely retrospective. The argument for their existence rests on three interconnected goals. The first is accountability – ensuring that perpetrators of mass atrocities face consequences rather than enjoying the protection of sovereignty or political power. The second is victims’ justice – giving victims formal recognition that crimes were committed against them and that those crimes mattered to the world. International criminal tribunals can contribute to the development and clarification of IHL; they can strengthen respect for IHL by providing justice for victims, act as a deterrent in future armed conflicts, and contribute to reconciliation and reconstruction by establishing the truth of what happened during a conflict.

The third goal is deterrence – making clear to future commanders and political leaders that the commission of mass atrocities carries personal criminal risk. Whether international courts have succeeded as deterrents is contested. The ICC cannot mount successful cases without state cooperation, which means it acts inconsistently in its selection of cases and is prevented from taking on hard cases, reducing its deterrent value. Critics and advocates alike acknowledge that the court’s reach is limited when major powers refuse to cooperate or remain outside the Rome Statute system entirely.

These limitations, however, do not undermine the underlying rationale for why international courts were needed in the first place. The question was never whether such courts would be perfect instruments. The question was whether, in the absence of international mechanisms, there would be any accountability at all for the perpetrators of the worst crimes known to humanity. History provided a clear answer to that question long before the ICC was built.

The bigger picture: international courts as a legal necessity 🔗

The growth of international courts reflects a maturation in the international legal order’s understanding of what states owe their own people and what the international community owes to victims when states default on that obligation. It reflects the recognition that the nature of modern armed conflict – with its internal wars, civilian targeting, and state-sponsored brutality – demands legal mechanisms that are not dependent on the goodwill of the very entities that may be committing the crimes. And it reflects the hard-won principle, established at Nuremberg and built upon ever since, that individuals bear personal responsibility for international crimes regardless of their official position.

The ICC, the ICTY, the ICTR, and the various hybrid tribunals that have followed are not perfect institutions. But their imperfections are the imperfections of any system of justice attempting to operate in a deeply unequal and politically fractured world. The reasons they exist remain as valid today as they were in 1945, and as the ongoing investigations into conflicts in Ukraine, Gaza, and elsewhere demonstrate, the need they were built to address has not diminished.

What do you think? If a state is both the perpetrator of atrocities and the authority responsible for prosecution, can justice ever be genuinely delivered without international intervention? And given the limitations that non-cooperation by powerful states places on the ICC, is a court that cannot enforce its own warrants still a meaningful mechanism for accountability?

References

1. https://www.un.org/en/genocideprevention/documents/atrocity-crimes/Doc.33_GC-EN.pdf
2. https://www.icrc.org/en/doc/war-and-law/treaties-customary-law/geneva-conventions/overview-geneva-conventions.htm
3. https://www.ohchr.org/en/instruments-mechanisms/instruments/rome-statute-international-criminal-court
4. https://www.icc-cpi.int/about/the-court
5. https://www.icty.org/
6. https://unictr.irmct.org/