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Mondial Summer 2020: Book Review

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Existing Legal Limits to Security Council Veto Power in the Face of Atrocity Crimes

By Jennifer Trahan, Clinical Professor of Law, New York University

Cambridge University Press, August 2020

Review by Fergus Watt

It is often assumed by casual observers of the United Nations that the power to veto resolutions on the maintenance of international peace and security wielded by the five permanent members of the UN Security Council (China, France, Russia, United Kingdom and the United States – the “P5) is untrammeled and simply a mater of their own discretion.

Not so. Jennifer Trahan’s latest book powerfully explains that when permanent members of the UN Security Council threaten or use their veto power to block measures aimed at preventing or punishing genocide, war crimes or crimes against humanity, they may be acting contrary to international law.

Whereas the veto may appear to be treated as a carte blanche (a permanent member may exercise the veto for whatever reason), the veto, created in the UN Charter, actually sits within a system of international law.

As Trahan illustrates, three distinct legal arguments, based on existing international law, demonstrate that there are in fact legal limits that constrain the use of the veto in the face of genocide, crimes against humanity, and/or war crimes.

  1. Jus cogens

Under international law jus cogens norms are, hierarchically, the highest level of law, from which no derogations are permitted and which must be respected in all circumstances. Because the veto is conferred upon the P5 by the UN Charter, it is subordinate to jus cogens in terms of the hierarchy of legal norms.

Legal prohibitions of genocide, crimes against humanity and war crimes are widely acknowledged as universal, jus cogens law. Consequently, use of the veto to prevent action by the Security Council in the face of these atrocity crimes is contrary to international law.

Trahan’s book cites numerous examples of unacceptable use of the veto, particularly in Syria and Darfur. The book also delves into the considerable power that accrues to the P5 in Council deliberations on account of their ability not only to wield, but also to threaten to use the veto.

  1. The Veto and the UN Charter

The veto is created by the UN Charter. But the Charter also provides limitations on the Security Council’s power. Under Article 24(2) the Council must act “in accordance with the purposes and principles of the United Nations.”

The purposes and principles of the UN, as outlined in articles 1 and 2 of the Charter, are quite broad. They include respecting “principles of justice and international law,” “promoting and encouraging respect for human rights,” and “good faith.”

Trahan points out that this argument as to limitations to veto use provided by the Charter has been reflected by a number of states in formal statements at the UN. This demonstrates that states have not acquiesced to a practice of unlimited veto use in the face of atrocity crimes; rather, states are persistently lodging objections to such veto use.

  1. The Veto and Foundational Treaties

Finally, Trahan reminds us that the treaty obligations of individual permanent member states — for instance under the Genocide Convention — include an obligation to “prevent” genocide.

Security Council members must respect these treaties. The permanent members are not free to act in complete disregard of these foundational treaty obligations.

Trahan’s work has been endorsed by a number of important legal scholars, including Hans Corell, the long-time UN Under Secretary-General for Legal Affairs. Although she is not the first person to make these arguments, her book provides a compelling case for a fresh look at these existing legal limits to the use of the veto by the P5.

Of course, those inclined toward a more realpolitik view of world affairs might argue that the actual exercise of the veto by the permanent members constitutes important precedent which should equally condition any understanding of when and under what circumstances the veto power may legitimately be used. Well, sure. Power politics co-exists uneasily alongside actual international legal obligations. The existence of legal obligations is no guarantee that they will be observed in practice.

This points to some of the important take-aways from a consideration of Trahan’s arguments. Governments and civil society organizations committed to strengthening the rule of law can take steps to strengthen observance of these “existing legal limits.” Trahan, to her credit, discusses many of the actions that can be considered. These include:

  • Seeking a ruling at the International Court of Justice clarifying legal issues surrounding use of the veto;
  • Empowering the Security Council’s non-permanent members, for example to strengthen their advocacy of Security Council “Codes of Conduct” and calls for veto restraint particularly in the face of atrocity crimes;
  • Strengthening the options for action through the General Assembly when the Security Council fails in its responsibilities to maintain international peace and security.

In a time of turmoil and change at the UN, Jennifer Trahan’s scholarly work provides much-needed clarity on some essential old truths, and points to measures that can strengthen a system better grounded in the rule of law.

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