The ASIL Centennial Annual Meeting Adopts a Resolution on the Use of Armed Force and the Treatment of Detainees
[Insight Editor's note: This Insight differs from the usual ASIL Insight in that it concerns an action taken by the ASIL itself. The action is significant because the American Society of International law, a nongovernmental organization with 4,000 members worldwide, rarely takes positions on substantive issues as a body, and because the matters covered in its resolution on the use of armed force and the treatment of detainees are central to the establishment and maintenance of international relations on the basis of law and justice - one of the primary objects of the ASIL. The resolution is accessible on line at www.asil.org/events/am06/resolutions.]
On March 30, 2006, for only the eighth time in its 100-year history, the American Society of International Law adopted a resolution on a subject of international law. The Resolution restates fundamental principles regarding the resort to and conduct of armed force, as well as to the rights of persons in detention. The Resolution received overwhelming support at the Annual General Meeting.
The topic of each paragraph of the Resolution was identified through active discussion over several months on the ASIL electronic Forum, facilitated by Ben Davis of the University of Toledo College of Law. Each topic relates to government action, both in the United States and abroad, that has either violated international law or has challenged the validity of a principle. It was to respond to these actions, to provide a clear restatement of the law, that the Resolution was proposed. The Resolution also responds to the implicit charge that international law is endlessly malleable, that its content can hardly be known or is rarely agreed upon, and, therefore, need not be respected. Adoption of the Resolution indicates that members of the American Society stand by these principles in this the Society's hundredth anniversary year.
This Insight provides basic legal authority for each paragraph of the Resolution.
1. Resort to armed force is governed by the Charter of the United Nations and other international law (jus ad bellum).
One of the greatest accomplishments of the Twentieth Century was the outlawing of the use of force by states as an instrument of national policy. The United Nations Charter is the principal source of legal rules on resort to armed force today. It is a multilateral treaty binding currently on 191 states.[1] It has been binding on the United States since 1945. The Charter was drafted largely by the United States following the Second World War to create an institution and a set of principles dedicated to the maintenance of peace and security in the world. The U.S. and its allies succeeded in creating a legal regime on resort to force that has withstood challenges for over 60 years. The Charter's core principle, the general prohibition on the use of force found in Article 2(4),[2] has evolved to the point that in 1986 the International Court of Justice recognized it as a principle of jus cogens, a peremptory norm-one not subject to contrary agreement by treaty.[3] The only exceptions to Article 2(4) provided in the Charter are the right to use force in self-defense, per Article 51, and the right to use force with Security Council authorization, as provided in Chapter VII. In September 2005, the vast majority of UN members re-affirmed their commitment to the Charter in general, and the rules on the use of force in particular, at the World Summit held in New York.[4]
In addition to the Charter, certain principles of customary international law and other treaties also contribute to the regulation of the use of armed force. For example, a state acting in lawful self-defense must use only such force as is necessary to defend itself. In other words, the right to use force even in lawful self-defense is not unlimited.[5] This principle is implicit in the Charter and is an established norm of customary international law. Thus, this paragraph of the Resolution refers to the jus ad bellum to incorporate all customary and conventional law that regulates the resort to force.
2. Conduct of armed conflict and occupation is governed by the Geneva Conventions of August 12, 1949, and other international law (jus in bello).
The four 1949 Geneva Conventions, like the UN Charter, are multilateral treaties enjoying near-universal state adherence, including by the United States.[6] According to common Article 2 of the four Conventions, they apply in cases of armed conflict and occupation involving parties to the Conventions. Their purpose is to protect the victims of armed conflict,[7] and they are intended to be applied generously with that purpose in mind. The ASIL Resolution cites the 1949 Geneva Conventions because of their importance and centrality to the jus in bello, parallel to the importance and centrality of the Charter to the jus ad bellum.
In addition to the 1949 Conventions, a number of other treaties and rules of customary international law are relevant to the conduct of armed conflict. These are referenced in the Resolution by the collective designation, the "jus in bello." It is well known that such important law as the Hague Regulations of 1907,[8] the 1977 Additional Protocols to the 1949 Conventions,[9] certain arms control conventions,[10] and principles of customary international law[11] are included in the term "jus in bello."
The International Court of Justice in its 1996 advisory opinion on the Legality of the Threat or Use of Nuclear Weapons said the following about the jus in bello:
The extensive codification of humanitarian law and the extent of the accession to the resultant treaties, as well as the fact that the denunciation clauses-have never been used, have provided the international community with a corpus of treaty rules the great majority of which had already become customary and which reflected the most universally recognized humanitarian principles. These rules indicate the normal conduct and behavior expected of states.[12]
3. Torture and cruel, inhuman, or degrading treatment of any person in the custody or control of a state are prohibited by international law from which no derogation is permitted.
The ASIL Resolution restates that torture, cruelty, inhumanity and degradation against persons in custody are unlawful under international law, whether in situations of armed conflict or peace.[13] Under Article 17 of the Third Geneva Convention (on prisoners of war), "No physical or mental torture, nor any other form of coercion, may be inflicted on prisoners of war to secure from them information of any kind whatever."[14] Under Article 31 of the Fourth Geneva Convention (on civilians): "No physical or moral coercion shall be exercised against protected persons, in particular to obtain information from them or from third parties."[15] At a minimum, all persons detained in an international armed conflict are entitled to the protections of Additional Protocol I, Article 75. Article 75 is part of customary international law, and, therefore, binding on all states. It prohibits torture as well as other violence to the life, health or well-being of persons, and outrages upon personal dignity. In non-international armed conflict, common Article 3 to the four Geneva Conventions also prohibits torture as well as other violence to life and person, including cruel treatment and outrages upon personal dignity. These are absolute prohibitions; there are no exceptions.
Outside of situations of armed conflict, peacetime human rights law regulates interrogation. It, too, prohibits torture, cruelty, inhumanity, and degradation. Article 5 of the Universal Declaration of Human Rights states that "no one shall be subjected to torture or to cruel, inhuman or degrading treatment or punishment."[16] This principle has been reconfirmed, restated and elaborated in a series of important treaties, including the International Covenant on Civil and Political Rights of 1966 (Article 7)(the United States is a party);[17] the American Convention on Human Rights (Article 5),[18] the European Convention for the Protection of Human Rights and Fundamental Freedoms (Article 3),[19] the Convention Against Torture (Articles 1, 2 and 16)(the United States is a party),[20] and the African (Banjul) Charter on Human and Peoples' Rights (Article 5).[21] The customary international law of human rights also prohibits torture as well as cruel, inhuman and degrading treatment.[22]
The Convention Against Torture (CAT) disallows necessity and other excuses as defenses to torture. Article 2(2) provides: "No exceptional circumstances whatsoever, whether a state of war or a threat of war, internal political instability or any other public emergency, may be invoked as a justification of torture." The CAT does not specifically disallow necessity as an excuse for lesser violations of the Convention, i.e., for cruel, inhuman and degrading treatment. The International Covenant on Civil and Political Rights (ICCPR), however, in providing for derogations during emergencies, prohibits derogation from Article 7 as a whole. In addition, the Committee of Ministers of the Council of Europe affirmed in July 2002, that "[t]he use of torture or of inhuman or degrading treatment or punishment is absolutely prohibited, in all circumstances, and in particular during the arrest, questioning and detention of a person suspected of 'terrorist activities, irrespective of the nature of the acts that the person is suspected of'."[23] Thus, torture, cruel, inhuman and degrading treatment are all considered non-derogable prohibitions even in times of national emergency.[24]
As part of customary international law, these principles bind states wherever they act. There is in customary international law no geographic restriction on the prohibition on torture or cruel, inhuman, and degrading treatment of persons in custody.
4. Prolonged, secret, incommunicado detention of any person in the custody or control of a state is prohibited by international law.
Again, the sources of this principle are found principally in the jus in bello for armed conflict situations and general human rights law applicable in the absence of armed conflict.[25]
To protect those lawfully detained in armed conflict, the 1949 Geneva Conventions on Prisoners of War and Civilians set out conditions of detention, including, most importantly, the right of Protecting Powers or the International Committee of the Red Cross (ICRC) to visit those detained. There is a provision in the Civilians Convention, Article 143, which allows a brief delay in gaining access to prisoners:
Such visits may not be prohibited except for reasons of imperative military necessity, and then only as an exceptional and temporary measure. Their duration and frequency shall not be restricted...
The ICRC's practice has been to accept no more than a two-week delay for access to individuals under the terms of Article 143's allowance for "imperative military necessity." This practice coincides with Article 136 of the Civilians Convention that requires notifying information bureaus and the ICRC (as the Central Information Agency) of measures taken respecting any protected person "within the shortest period possible." This applies to any person to be detained for more than two weeks.[26] In addition to reporting measures taken against protected persons, Article 136 also requires that a Detaining Power provide information bureaus and the ICRC "promptly with information concerning all changes pertaining to these protected persons, as, for example, transfers, releases, repatriations, escapes, admittances to hospitals, births and deaths." Article 136 contains no exception for military necessity.
In peacetime, persons in detention, again, are covered by the series of human rights treaties discussed above with respect to torture, cruel, inhuman and degrading treatment. The ICCPR allows for derogation from the detention protections found in Article 9 during a national emergency, but formal steps must be taken if derogations are claimed. The United States has not formally derogated from its ICCPR detention obligations.[27] Even when a state derogates, however, derogation is lawful only "to the extent strictly required by the exigencies of the situation."[28] This restriction has led courts to apply a test of proportionality as to the length of time a person may be held in preventive detention. The Inter-American Court of Human Rights decided in 1999 in Castillo Petruzzi v. Peru that a 30-day period, 15 days renewable once, of incommunicado preventive detention violated Article 7(5) of the American Convention (requiring that any detained person be brought promptly before a judge) despite Peru's derogation with respect to that article.[29] Other limits on permissible detention even under declared states of emergency are discussed in two advisory opinions of the Inter-American Court: Habeas Corpus in Emergency Situations and Judicial Guarantees in States of Emergency.[30]
The European Court of Human Rights has reviewed preventive detention, but not in cases where no judicial remedy was available. In Brogan it found that a period of about four days without being brought before a judge was inconsistent with the European Convention on Human Rights, Article 5, even as an anti-terrorism measure.[31] In response to this decision, the UK derogated from Article 5 and ICCPR Article 9. The Court found in a subsequent UK case, Brannigan, that a six day period of preventive detention did not violate the Convention, given the proper derogation in place. The UK, however, provided a right of habeas corpus.[32] In December 2004, in the Belmarsh Detentions case, the United Kingdom House of Lords ruled that indefinite detention pending deportation was disproportionate even in a time of emergency, and, thus violated ICCPR Article 9 (on the rights of those deprived of liberty).[33]
The UN Human Rights Committee, the body that administers the ICCPR, issues General Comments interpreting key provisions of the Covenant. In one of its General Comments it said, "Measures derogating from the provisions of the Covenant must be of an exceptional and temporary nature."[34]
There is a question whether the ICCPR applies to a government's acts outside its own territory. The Human Rights Committee, however, takes the position that states parties to the Covenant must apply its provisions to anyone within their effective control, even if not situated within their own territory.[35]
5. Standards of international law regarding treatment of persons extend to all branches of national governments, to their agents, and to all combatant forces.
The law of state responsibility provides the rules for determining when a state has committed a wrong under international law-whether a human rights violation or other type of wrong. The law of state responsibility makes clear that the acts of the state extend to organs exercising "legislative, executive, judicial or any other functions, whatever position it holds in the organization of the State, and whatever its character as an organ of the central government or of a territorial unit of the state."[36] Acts of state are also those of persons or entities "empowered by law" to exercise elements of governmental authority.[37] And of great importance:
The conduct of a person or group of persons shall be considered an act of a State under international law if the person or group of persons is in fact acting on the instructions of, or under the direction or control of, that State in carrying out the conduct.[38]
The case of Prosecutor v. Tadic from the International Criminal Tribunal for the former Yugoslavia (ICTY) provides an additional ground for finding the acts of an armed group to be the responsibility of the state:
"[t]he control required by international law may be deemed to exist when a State (or, in the context of an armed conflict, the party to the conflict) has a role in organizing, coordinating or planning the military actions of the military group, in addition to financing, training and equipping or providing operational support to that group."[39]
When the United States and United Kingdom held Afghanistan's de facto government responsible for the acts of al Qaeda in 2001, the attribution appeared to meet the test in Tadic. Few if any states protested the claim of responsibility.
The Resolution also restates that international law applies directly to "all combatant forces." "Combatant forces" is a broad term that encompasses anyone engaged in an armed conflict.[40] An armed conflict exists when there is significant fighting by organized armed groups and when the armed groups either have a connection to a state or exercise control over territory. The 1998 Statute of the International Criminal Court makes clear that international law, in particular the jus in bello, applies to groups engaged in armed conflict.[41]
6. In some circumstances, commanders (both military and civilian) are personally responsible under international law for the acts of their subordinates.
Under the doctrine of command responsibility in international law, leaders may be held criminally liable for the acts of subordinates:
The doctrine encompasses two different forms of liability. The first is direct or active command responsibility-when the leader takes active steps to bring about the crime by, for example, ordering his subordinates to do something unlawful...
The second type of command responsibility (and the one to which people usually refer when they speak generally of "command responsibility"), involves "indirect" or "passive" command responsibility. Because direct proof that a commander actually ordered his troops to commit crimes is not always forthcoming, the second type of command responsibility is more significant in both theory and practice as a distinct theory of liability.[42]
At the time of writing, the latest precedent as to the standard of command responsibility under international law is found in a decision of the ICTY, Prosecutor v. Timor Blaskic. The case concerned criminal liability for indirect or passive command responsibility during the conflict in the former Yugoslavia.
The Appeals Chamber ... holds that a person who orders an act or comission with the awareness of the substantial likelihood that a crime will be committed in the execution of that order, has the requisite mens rea for establishing liability under Article 7(1) [of the Statute of the ICTY] pursuant to ordering. Ordering with such awareness has to be regarded as accepting that crime.[43]
7. All states should maintain security and liberty in a manner consistent with their international law obligations.
The International Court of Justice has stated in several cases that international law prevails over the domestic or municipal law of states. It is a "fundamental principle that international law prevails over domestic law."[44] If a rule of domestic law and a rule of international law are in conflict with each other, a national government might act lawfully under its own domestic law but will still be responsible at the international level for violating any conflicting rule of international law.
Mary Ellen O'Connell, an ASIL member, holds the Robert and Marion Short Chair in Law at the Notre Dame Law School. She is the author of International Law and the Use of Force (2005), co-editor of Redefining Sovereignty, The Use of Force After the Cold War (2005), and the author of numerous articles on international law and the use of force. She was formerly a Title X professor for the U.S. Department of Defense. She co-chaired the 2002 Annual Meeting of the American Society of International Law. She currently chairs the International Law Association Study Committee on the Use of Force.
She thanks Rich Edwards, José Alvarez and Rick Kirgis for helpful comments.
Footnotes
[1] For the text of the Charter and the current members, see the UN website, www.un.org.
[2] Article 2(4) says, "All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations."
[3] Military and Paramilitary Activities In and Against Nicaragua 1986 I.C.J. para. 190 (Nicar. v. U.S.) (June 27). In the same paragraph the ICJ referred to citations by the United States in a memorial to the status of Article 2(4) as a rule of jus cogens.
[4] 2005 World Summit Outcome, GA Res 60/1, UN GAOR, 60th Sess., UN Doc. A/RES/60/1 (2005) at 2.
[5] Oil Platforms (Iran v. U.S.) 2003 I.C.J., (Nov. 6) para. 74, citing Nicaragua supra note 2, para. 194. See also, Judith Gardam, Necessity and Proportionality and the Use of Force by States (2004) and Christopher Greenwood, The Relationship between ius ad bellum and ius in bello, 9 Rev. Int'l Stud. 221, 223 (1983).
[6] Convention (I) for the Amelioration of the Condition of the Wounded and Sick in Armed Forces in the Field, Geneva, 12 August 1949, 75 U.N.T.S. 31, 6 U.S.T. 3114; Convention (II) for the Amelioration of the Condition of Wounded, Sick and Shipwrecked Members of Armed Forces at Sea, Geneva, 12 August 1949, 75 U.N.T.S. 85, 6 U.S.T. 3217; Convention (III) relative to the Treatment of Prisoners of War, Geneva, 12 August 1949, 75 U.N.T.S. 135, 6 U.S.T. 3316; and Convention (IV) relative to the Protection of Civilian Persons in Time of War, Geneva, 12 August 1949, 75 U.N.T.S. 287, 6 U.S.T. 3516. For the texts of the Conventions and current parties, go to the website of the International Committee of the Red Cross, www.icrc.org.
[7] Frits Kalshoven, Constraints on the Waging of War 40 (1987).
[8] Convention Respecting the Laws and Customs of War on Land (1907 Hague Convention IV), Oct. 18, 1907, Annex, 36 Stat. 2277, T.S. No. 539, 1 Bevans 631.
[9] Protocol Additional to the Geneva Conventions of 12 August 1949, and Relating to the Protections of Victims of International Armed Conflicts (Protocol I) of 8 June 1977, 1125 U.N.T.S. 3; Protocol Additional to the Geneva Conventions of 12 August 1949, and Relating to the Protections of Victims of Non-International Armed Conflicts (Protocol II) of 8 June 1977, 1125 U.N.T.S. 610. For the texts of the Conventions and current parties, go to the website of the International Committee of the Red Cross, www.icrc.org. As of December 2005 Additional Protocol I had 163 parties; Additional Protocol II had 159 parties. The United States is not a party to either Protocol, but has signed Additional Protocol II and takes the official position that much of Additional Protocol I is customary international law. Michael Matheson, Session One: The United States Position on the Relation of Customary International Law to the 1977 Protocols Additional to the 1949 Geneva Conventions, 2 Am. U. J. Int'l L.& Pol' Y 419-31 (1987); see also Jordan J. Paust, Executive Plans and Authorizations to Violate International Law Concerning Treatment and Interrogation of Detainees, 43 Colum. J. Trans'l. L. 811, 818 (2005).
[10] For a thorough discussion of restrictions on weapons and the relationship of these restrictions to other jus in bello rules, see the Legality of the Threat of Use of Nuclear Weapons, 1996 I.C.J. (Ad. Op.)(July 8).
[11] See I & II Customary International Humanitarian Law (Jean-Marie Henckaerts & Louise Doswald-Beck eds., 2005).
[12] Nuclear Weapons, supra note 10, para. 82.
[13] See generally Mary Ellen O'Connell, Affirming the Ban on Harsh Interrogation, 66 Ohio St. L. J. 1231 (2005).
[14] Prisoners Convention, supra note 6, art. 17.
[15] Civilians Convention, supra note 6, art. 31.
[16] Universal Declaration on Human Rights, United Nations G.A. Res. 217A(III), 3rd Sess., art. 5, U.N. Doc. A/RES/3/217 (1948).
[17] International Covenant on Civil and Political Rights, Dec. 16, 1966, 999 U.N.T.S. 171 [hereinafter ICCPR].
[18] American Convention on Human Rights, opened for signature Nov. 22, 1969, 1144 U.N.T.S. 123.
[19] European Convention for the Protection of Human Rights and Fundamental Freedoms, opened for signature April 11, 1950, 213 U.N.T.S. 222, available at http://conventions.coe.int/Treaty/en/Treaties/Html/005.htm.
[20] U.N. Convention Against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment,
U.N. GAOR, 39th Sess., Supp. No. 51, at 197, U.N. Doc. A/39/51 (1984).
[21] African (Banjul) Charter on Human and Peoples' Rights of June 27, 1981, OAU Doc. CAB/LEG/67/3 rev. 5, 21 I.L.M. 58 (1982).
[22] See Restatement (Third) of the Foreign Relations Law of the United States, sec. 702 (1987), "Customary International Law of Human Rights, A state violates international law if, as a matter of state policy, it practices, encourages or condones...(d) torture or other cruel, inhuman or degrading treatment or punishment."
[23] Guidelines on Human Rights and the Fight Against Terrorism, cited in Jeremy Waldron, Torture and Positive Law: Jurisprudence for the White House, at 7, n.17, at http://www.columbia.edu/cu/law/fed-soc/otherfiles/waldron.pdf.
[24] ICCPR, supra note 17, Art. 4.
[25] See Frederic Kirgis, Alleged Secret Detention of Terrorist Suspects, 10 ASIL Insight, Feb. 14, 2006, at http://www.asil.org/insights/2006/02/insights060214.html
[26] See also, Civilians Convention, supra note 6 , Arts. 137-140.
[27] Diane Amman, Addendum to Frederic Kirgis, Alleged Secret Detention of Terrorist Suspects, supra note 25.
[28] ICCPR, supra note 17, art. 4.
[29] Castillo Petruzzi v. Peru, Inter-Am. Ct. H.R. Series C. No. 52 (1999). Paolo Carozza and Douglass Cassel brought this and other cases to my attention. They also provided helpful comments on the question of secret detention, as did Hurst Hannum and John Quigley.
[30] Habeas Corpus in Emergency Situations (Arts. 27(2), 25(1) and 7(6) of the American Convention on Human Rights). Inter-Am. Ct. H.R., Advisory Opinion OC-8/87 (1987); Judicial Guarantees in States of Emergency (Arts. 27(2), 25 and 8 of the American Convention on Human Rights), Inter-Am. Ct. H.R. Advisory Opinion OC-9/87 (1987). Cited in Joan Fitzpatrick, Speaking Law to Power, The War Against Terrorism and Human Rights, 14 Eur. J. Int'l L. 241 (2003).
[31] Brogan and Others v. United Kingdom, 145-B Eur. Ct. H. R. (ser. A)(1988), at para. 62 (1988).
[32] Brannigan and McBride v. United Kingdom, 258 Eur. Ct. H. R. (ser. A)(1993). See also Human Rights Committee, General Comment No. 29: States of Emergency, UN Doc. CCPR/C/21/Rev.1/Add.11 (2001).
[33] A (FC) and others; (X) FC and another v. Secretary of State for the Home Department (Belmarsh), 2004 UKHL 56. See also Sangeeta Shah, The UK's Anti-Terror Legislation and the House of Lords: The First Skirmish, 5 Hum. Rts. L. Rev. 403 (2005).
[34] UN Doc. CCPR/C/21/Rev.1/Add. 11, para. 2 (2001).
[35] See Kirgis, supra note 25.
[36] Articles on Responsibility of States for International Wrongful Acts, art. 4, adopted by the International Law Commission at its 53rd Sess. (2001); Resolution of the United Nations General Assembly on the Responsibility of States for Internationally Wrongful Acts (Dec. 12, 2001), UN Doc. A/RES/56/83[hereinafter Articles on State Responsibility]. See also James Crawford, The International Law Commission's Articles on State Responsibility: Introduction, Text and Commentaries (2002).
[37] Articles on State Responsibility, supra note 36, art. 5.
[38] Id. at article 8.
[39] Prosecutor v. Tadic, Judgment, No. IT-94-1-A, para. 137 (July 15, 1999), at http://www.un.org/icty/tadic/appeal/judgment/index.htm
[40] Some reserve the term "combatant" for lawful combatants, persons with a right to engage in armed conflict such as members of the regular armed forces of a state.
[41] International Criminal Court Statute, Art. 8, July 17, 1998, UN Doc. A/CONF.183/9, 37 ILM 999-1019 (1998).
For more on the international law governing combatant forces and other violent non-state actor groups, see European Commission for Democracy Through Law (Venice Commission) On the International Legal Obligations of Council of Europe Member States in Respect of Secret Detention Facilities and Inter-State Transport of Persons, Mar. 17, 2006, Op. no. 363/2005, CDL-AD (2006)009, citing Prosecutor v. Tadic (1996) 105 I.L.R. 419, 488 and quoting, The Manual of the Law of Armed Conflict, UK Ministry of Defence, Oxford (OUP) 2004, no. 3.5.1 (at p. 31). See also Mary Ellen O'Connell, Enhancing the Status of Non-State Actors Through a Global War on Terror?, 43 Col. J. Trans. L. 435 (2005), and Christopher Greenwood, War, Terrorism and International Law, 56 Curr. Leg. Probs. 505, 529 (2004).
[42] Allison Marston Danner & Jenny S. Martinez, Guilty Associations: Joint Criminal Enterprise, Command Responsibility, and the Development of International Criminal Law, 93 Cal. L. Rev. 75, 120 (2005).
[43] IT-95-14-A, para. 42, July 29, 2004. Article 7(1) of the ICTY Statute says: "A person who planned, instigated, ordered, committed or otherwise aided and abetted in the planning, preparation or execution of a crime referred to in articles 2 to 5 of the present Statute, shall be individually responsible for the crime."
[44] Applicability of the Obligation to Arbitrate Under Section 21 of the United Nations Headquarters Agreement of 26 June 1947, 1988 I.C.J. 12, 34 (Apr. 26). See also Vienna Convention on the Law of Treaties, opened for signature May 23, 1969, art. 27, 1155 UNTS 331.