(Editor’s Note: This article is part of a series on a proposed Convention on the Prevention and Punishment of Crimes Against Humanity, due to be considered in discussions that resume on Oct. 13 in the Sixth Committee, the U.N. General Assembly’s primary forum for discussion of legal questions.)

It is a matter of historical curiosity that the U.N. General Assembly adopted the Genocide Convention in 1948 without a corresponding treaty for crimes against humanity. Unlike the then-new crime of genocide, crimes against humanity had already been recognized in 1945 in Article 6(c) of the Charter of the International Military Tribunal (“IMT”), which applied to the Nuremberg trials against the major Nazi leaders, and in Article II(1)(c) of Control Council Law No. 10, which applied to subsequent prosecutions. The term “genocide” had been introduced by Raphaël Lemkin just one year earlier in 1944 in his book “Axis Rule in Occupied Europe.” It was still more a description of Nazi crimes than a legal definition. The IMT Tribunal did not recognize the neologism in the 1946 Nuremberg Judgment. It was only mentioned in passing by the U.S. Military Tribunal in the 1947 Nuremberg “Justice Trial” as “the prime illustration of a crime against humanity.”

Some 50 years later, in the 2000 Kupreškić Judgment, a Trial Chamber of the International Criminal Tribunal for the former Yugoslavia (“ICTY”) reaffirmed that “persecution as a crime against humanity is an offence belonging to the same genus as genocide.  … [W]hen persecution escalates to the extreme form of wilful and deliberate acts designed to destroy a group or part of a group, it can be held that such persecution amounts to genocide.”  In this light, a codification of crimes against humanity in a U.N. convention with the addition of the new crime of genocide as a species of persecution would have been more logical in 1948. So why was a treaty on genocide adopted without one for crimes against humanity?

Crimes against humanity was a revolutionary concept in 1945. Unlike war crimes, which are generally committed against nationals of an adversary, these crimes could be committed against “any civilian population,” irrespective of nationality. The concept filled a conspicuous lacuna that situated Holocaust victims belonging to the European Axis States beyond the scope of international criminal law. Article 6(c) of the IMT Charter limited the jurisdiction of the Tribunal to crimes against humanity committed “in execution of or in connection with” crimes against peace or war crimes. Without a nexus to war, the IMT Charter would have criminalized human rights violations in peacetime – an unprecedented and unacceptable encroachment on sovereignty at the time. Thus, although the Nuremberg Tribunal found that “[t]he policy of persecution, repression and murder of civilians in Germany before the war of 1939 … was most ruthlessly carried out,” it held that “revolting and horrible as many of these crimes were, it has not been satisfactorily proved that they were done in execution of, or in connection with” aggressive war or war crimes.

Shaped By a Limitation

The proposal to adopt a Genocide Convention was shaped by this limitation in the definition of crimes against humanity under the IMT Charter. It was dissatisfaction with the Tribunal’s failure to exercise jurisdiction over pre-1939 persecutions that motivated some to propose the criminalization of “peacetime genocide” in a treaty. Supporters of this initiative emphasized that less serious offences committed in time of peace – such as piracy, trade in women and children, trafficking in drugs, etc. – were already recognized as international crimes. Others, however, opposed genocide as a “useless and dangerous neologism” insisting that it was simply a form of crimes against humanity.

This debate shaped the decision to separate the two crimes. Thus, General Assembly Resolution 95(I) called for the codification of the Nuremberg Principles in an “International Criminal Code” – including the Article 6(c) definition with a link to war – while Resolution 96(I) called for drafting a Genocide Convention that – upon its adoption in 1948 – defined genocide as an international crime “whether committed in time of peace or in time of war.”  Had Article 6(c) not required a nexus with armed conflict, genocide would probably have been subsumed by the Nuremberg Principles without a separate treaty.

It is remarkable that in 1995 – exactly 40 years after the IMT Charter – the ICTY Appeals Chamber held in the Tadić case that the Article 6(c) nexus requirement “was peculiar to the jurisdiction of the Nuremberg Tribunal” and that “[i]t is by now a settled rule of customary international law that crimes against humanity do not require a connection to international armed conflict.”  This was subsequently confirmed by the authoritative definition in Article 7 of the Statute of the International Criminal Court (“ICC”) adopted at the Rome Diplomatic Conference in 1998.

The absence of a treaty on crimes against humanity is not without consequence. The ICC Statute leaves unaddressed the obligation of States to prevent and punish crimes against humanity. The “complementarity principle” simply means that genuine national proceedings render a case inadmissible before the ICC; unlike the provisions of the 1948 Genocide Convention, the ICC Statute does not establish any obligation of states parties to prosecute international crimes before their national courts. A crimes against humanity treaty could address this gap.  Furthermore, without a treaty, there is no compromissory clause allowing for enforcement of such obligations before the International Court of Justice (“ICJ”) in respect of crimes against humanity. By contrast, the Genocide Convention’s Article IX has enabled important proceedings such as the Application of Genocide Convention case initiated by The Gambia against Myanmar in 2019 (see our forum series here).

Filling a Conspicuous Gap

The need for a crimes against humanity treaty is all the more apparent when considering that an isolated war crime of murder or peacetime crime of torture triggers obligations of repression under the 1949 Geneva Conventions and 1984 Convention Against Torture, respectively, whereas – to give but one example – the crime against humanity of widespread or systematic murder against a civilian population in peacetime falls into a treaty void. As a “catch all” crime covering a broad spectrum of atrocities, a treaty on crimes against humanity would fill this conspicuous gap, and make a significant contribution to the consolidation and rationalization of disparate international criminal law treaties.

Some might argue that it is not important to have a Crimes Against Humanity Convention because the Genocide Convention already addresses “the crime of crimes.” It is a misconception, however, that crimes against humanity is somehow a lesser offence than genocide in international law. First, the exclusion of political and social groups from the protections of the Genocide Convention means, for example, that the systematic murder, enslavement, and starvation of “class enemies” by the Khmer Rouge qualify as crimes against humanity but not genocide. It cannot be said that these heinous atrocities are somehow less grave merely because the label of genocide does not apply.

Second, it cannot be said in abstracto that just as murder is categorically more serious than assault in national laws, genocide is necessarily more serious than crimes against humanity. For instance, because genocide requires an intention to physically or biologically destroy a group, the killing of a hundred members of an ethnic group by a militia leader in a small village could qualify as genocide whereas the mass deportation of a million members of the same group (i.e. without an intention to destroy the group) by a head of state might only qualify as crimes against humanity. It cannot be said that the former is inherently more serious than the latter. The sentencing practice of international criminal tribunals suggests that genocide is more serious than crimes against humanity only when applied to the same perpetrator in respect of the same acts. The discourse that relegates any mass atrocity that doesn’t qualify as genocide to a black hole of “second best” remains oblivious to the compelling historical legacy and serious gravity of crimes against humanity.

It is time for the U.N. to reunite genocide with its genus by concluding a parallel treaty. The International Law Commission (“ILC”) draft Convention on the Prevention and Punishment of Crimes Against Humanity before the U.N. General Assembly provides a unique opportunity to finally address this glaring omission in the architecture of global justice.

IMAGE: Norng Chan Phal, who survived internment at the Tuol Sleng prison known as S-21 as a child, looks at portraits of victims of the Khmer Rouge regime displayed at Tuol Sleng genocide museum in Phnom Penh on September 2, 2020.  (Photo by TANG CHHIN SOTHY/AFP via Getty Images)