International humanitarian law (IHL) or ‘the law of armed conflict’ refers to the rules of
international law that govern the conduct of participants in an armed conflict, including the rules that determine the way in which force may be used during conflict. This branch of international law attempts to
alleviate the calamities of war by regulating the means and methods of warfare and
extending some protection to victims of armed conflict.
While it is impossible to completely eliminate the suffering caused by war, humanitarian law attempts to minimise that suffering without undermining military effectiveness. International humanitarian law applies equally to all parties to an armed
conflict. In other words, its application does not depend on whether a particular party is an aggressor state or is a state acting in self-defence.1
International criminal law provides a means for the enforcement of international
humanitarian law in addition to seeking to repress widespread violation of human rights
and mass atrocity. This Handbook provides an overview of
the sources of international humanitarian law (where is IHL found?), its applicability
(when and where does IHL apply?), and its key features and principles (what is involved
in IHL?), such as the distinction between combatants and civilians and the law
regulating the conduct of hostilities.
The Handbook then turns to the relationship between IHL and human rights law, examining
the extent to which human rights law applies in time of armed conflict and how that
body of law interacts with IHL. Finally, the Handbook examines international criminal
law with a particular focus on the jurisdiction of the International Criminal Court.
The development of international criminal law
The concept of international crimes initially developed in relation to piracy (acts of
violence committed for private ends on the high seas against another ship or its
passengers). Since piracy occurred on the high seas, i.e. in an area in which no state had
jurisdiction, all states were given jurisdiction to apprehend and try pirates – who were
regarded as the enemy of all mankind. In the late nineteenth century, states began
to take the view that violations of the emerging law of armed conflict engaged the
criminal responsibility of the individual who had committed the violation. Accordingly,
some states engaged in the trial of enemy personnel who had committed violations
of the laws and customs of war or of their own soldiers.
Thus, there were prosecutions by the United States at the end of the
American Civil War and during the US-armed conflict in the Philippines in 1902. At the end
of World War I, the Treaty of Versailles (with Germany) and the Treaty of Sèvres (with
Turkey) provided for war crimes trials. The Treaty of Versailles (Art. 227–230) provided
for the prosecution of Kaiser Wilhelm II before a special tribunal ‘for a supreme
offence against international morality and the sanctity of treaties’. However, the Kaiser
fled to the Netherlands and was never tried.
Although the treaty also recognised the right of the Allies to establish military
tribunals to try German soldiers accused of war crimes, instead a compromise was
reached under which Germany tried some of those accused of crimes – the ‘Leipzig
Trials’. Similarly, the Treaty of Sèvres was not ratified by Turkey and its replacement, the
Treaty of Lausanne, did not provide for war crimes prosecutions.
The main catalyst for the development of international criminal law was the
establishment by the victorious Allied powers at the end of World War II of the
International Military Trial at Nuremburg and the Tokyo International Criminal Tribunal.
The Nuremburg Tribunal was established by the governments of France, the UK, the USA
and the USSR ‘acting in the interests of all of the United Nations’ to try German leaders
for war crimes, crimes against peace, and crimes against humanity. In addition, Control
Council Law No. 10 provided for trials before military tribunals run by the occupying Allies
or before German courts. This resulted in a large number of prosecutions.
International criminal tribunals were next established in the 1990s by the UN Security
Council. During Yugoslavia’s disintegration in the early 1990s, war broke out among the
various factions and a number of significant atrocities were committed. In 1993, the
UN Security Council, by Resolution 827, set up an International Criminal Tribunal
for the Former Yugoslavia. That tribunal was established to deal with serious
international crimes committed since 1991 on the territory of the former Yugoslavia
and is based in The Hague. In 1994, the UN Security Council, by Resolution 955, set up
an International Criminal Tribunal in Arusha, Tanzania, to try crimes committed during
the genocide in Rwanda in which nearly a million people died.
As both tribunals were created by the UN Security Council all states have an obligation
International Humanitarian Law and International Criminal Justice: An Introductory Handbook 9
to co-operate with them. These two tribunals are ad hoc in the sense that they
are created to deal with crimes committed
within a particular location and within a particular time period. Moreover, they were
established after the fact. Both tribunals are now winding down after concluding the vast
majority of their cases.
In addition to these international criminal tribunals, there are a number
of ‘internationalised’, ‘mixed’ or ‘hybrid’ tribunals. These are tribunals established
to prosecute those who are alleged to have committed international crimes where the
tribunals are part international and part domestic. Examples include:
• The Special Court for Sierra Leone:
established by agreement between the
United Nations and the Government of
Sierra Leone to prosecute international
and national crimes committed in the war
in that country.
• Special Panels for Serious Crimes:
established in East Timor when that
country was recognised by the UN.
• Extraordinary Chambers in the courts of
Cambodia: established to deal with the
crimes against humanity committed in
Cambodia by the Khmer Rouge in the
1970s in which about 2 million people are
estimated to have died.
• ‘Regulation 64’ Panels in the courts of
• The Special Tribunal for Lebanon.
These tribunals are described as hybrid
or mixed because the judges and staff of
the tribunal are partly international and
partly drawn from the country concerned;
and the tribunals apply international law as
well as national law. The manner in which
these tribunals are established is varied.
Some are established by international
agreements (e.g. Sierra Leone), others are
established by domestic law but with the
support of the international community
(e.g. Cambodia), and others are established
by domestic law but at a time when the
country is being administered by the UN
(e.g. East Timor and Kosovo).