Rule 144. Ensuring Respect for International Humanitarian Law Erga Omnes
Rule 144. States may not encourage violations of international humanitarian law by parties to an armed conflict. They must exert their influence, to the degree possible, to stop violations of international humanitarian law.
Summary
State practice establishes this rule as a norm of customary international law applicable in both international and non-international armed conflicts.
International and non-international armed conflicts
Common Article 1 of the Geneva Conventions provides that States parties undertake to “ensure respect for the present Convention”.[1]  The same provision is repeated in Additional Protocol I in relation to respect for the provisions of that Protocol.[2]  Additional Protocol I further provides that in the event of serious violations of the Protocol, States parties undertake to act, jointly or individually, in cooperation with the United Nations and in conformity with the Charter of the United Nations.[3]  A similar provision is included in the Second Protocol to the Hague Convention for the Protection of Cultural Property.[4] 
Beginning with its commentary on common Article 1 of the Geneva Conventions, the ICRC has repeatedly stated that the obligation to “ensure respect” is not limited to behaviour by parties to a conflict, but includes the requirement that States do all in their power to ensure that international humanitarian law is respected universally.[5] 
The interpretation that common Article 1 involves obligations beyond those of the parties to the conflict was supported by the UN Security Council in a resolution adopted in 1990 calling on States parties to the Fourth Geneva Convention to ensure respect by Israel for its obligations, in accordance with Article 1 of the Convention.[6]  The UN General Assembly has adopted several resolutions to the same effect and in relation to the same conflict.[7]  Other international organizations have likewise called on their member States to respect and ensure respect for international humanitarian law, in particular the Council of Europe, NATO, the Organization of African Unity and the Organization of American States.[8] 
International conferences have similarly appealed to States to ensure respect for international humanitarian law. In 1968, the International Conference on Human Rights in Teheran adopted a resolution noting that States parties to the Geneva Conventions sometimes failed “to appreciate their responsibility to take steps to ensure the respect of these humanitarian rules in all circumstances by other States, even if they are not themselves directly involved in an armed conflict”.[9]  In the Final Declaration adopted by the International Conference for the Protection of War Victims in 1993, the participants undertook “to act in cooperation with the UN and in conformity with the UN Charter to ensure full compliance with international humanitarian law in the event of genocide and other serious violations of this law” and affirmed their responsibility, “in accordance with Article 1 common to the Geneva Conventions, to respect and ensure respect for international humanitarian law in order to protect the victims of war”. They further urged all States to make every effort to “ensure the effectiveness of international humanitarian law and take resolute action, in accordance with that law, against States bearing responsibility for violations of international humanitarian law with a view to terminating such violations”.[10]  More recently, the Conference of High Contracting Parties to the Fourth Geneva Convention in 2001 welcomed and encouraged initiatives by States, both individually and collectively, aimed at ensuring respect for the Convention.[11] 
Practice shows that the obligation of third States to ensure respect for international humanitarian law is not limited to implementing the treaty provision contained in common Article 1 of the Geneva Conventions and Article 1(1) of Additional Protocol I. For example, the ICRC’s appeals in relation to the conflict in Rhodesia/Zimbabwe in 1979 and to the Iran–Iraq War in 1983 and 1984 involved calls to ensure respect for rules not found in the Geneva Conventions but in the Additional Protocols (bombardment of civilian zones and indiscriminate attacks) and the countries alleged to be committing these violations were not party to the Protocols.[12]  It is significant that these appeals were addressed to the international community, that no State objected to them and that several States not party to the Additional Protocols supported them.[13] 
In the Nicaragua case (Merits) in 1986, the International Court of Justice held that the duty to respect and ensure respect did not derive only from the Geneva Conventions, but “from the general principles of humanitarian law to which the Conventions merely give specific expression”. The Court concluded, therefore, that the United States was “under an obligation not to encourage persons or groups engaged in the conflict in Nicaragua to act in violation of the provisions of Article 3 common to the four 1949 Geneva Conventions”.[14]  Similarly, according to the Draft Articles on State Responsibility, “a State which aids or assists another State in the commission of an internationally wrongful act by the latter is internationally responsible for doing so”.[15]  In several cases, national courts have rejected claims that this rule would prevent States from deporting persons to countries where violations of common Article 3 of the Geneva Conventions were allegedly occurring.[16] 
With respect to any positive obligations imposed by the duty to ensure respect for international humanitarian law, there is agreement that all States have a right to require respect for international humanitarian law by parties to any conflict. The Trial Chamber of the International Criminal Tribunal for the former Yugoslavia stated in its judgments in the Furundžija case in 1998 and Kupreškić case in 2000 that the norms of international humanitarian law were norms erga omnes and therefore all States had a “legal interest” in their observance and consequently a legal entitlement to demand their respect.[17]  State practice shows an overwhelming use of (i) diplomatic protest and (ii) collective measures through which States exert their influence, to the degree possible, to try and stop violations of international humanitarian law.[18] 
(i) Diplomatic protest. There is extensive practice, especially over the last two decades, of States objecting to violations of international humanitarian law by other States. These objections concern both international and non-international armed conflicts. They are not limited to violations of the Geneva Conventions and are often in relation to conflicts with which the protesting States have no specific connection. These objections have been made through bilateral diplomatic protests, in international fora or by means of resolutions of international organizations. They are usually directly aimed at the violating parties. Such protests have, on occasion, referred specifically to the duty of States, under common Article 1 of the Geneva Conventions, to ensure respect for international humanitarian law. The practice in this regard is catalogued in the context of the various rules covered by this study.
(ii) Collective measures. Apart from resolutions by international bodies, collective measures by States to try to “ensure respect” have taken the form, inter alia, of holding international conferences on specific situations, investigating possible violations, creating ad hoc criminal tribunals and courts, creating the International Criminal Court, imposing international sanctions and sending of peacekeeping or peace-enforcement troops. This practice is catalogued throughout this study in connection with each rule.
It should also be noted that States’ obligation to establish universal jurisdiction over grave breaches (see commentary to Rule 157) and their obligation to investigate war crimes falling within their jurisdiction and to prosecute the suspects if appropriate (see Rule 158) illustrate how respect for international humanitarian law can be enforced through the action of third States.
Lastly, it should be noted that neither the intention of the drafters of common Article 1 of the Geneva Conventions, nor practice since then, justifies the obligation to ensure respect for international humanitarian law being used as the sole basis for resort to the use of force. It is therefore expected that measures aimed at ensuring respect, beyond those decided by the UN Security Council, be peaceful ones. Additional Protocol I provides that in the event of serious violations of the Protocol, States parties undertake to act, jointly or individually, in cooperation with the United Nations and in conformity with the Charter of the United Nations.[19]  By referring to measures in conformity with the Charter of the United Nations, the Protocol makes it clear that States cannot use force in a manner unauthorized by the Charter to ensure respect for international humanitarian law. The same reasoning applies to Article 31 of the Second Protocol to the Hague Convention for the Protection of Cultural Property, which contains a similar provision.

[1] Geneva Conventions, common Article 1 (cited in Vol. II, Ch. 41, § 1).
[2] Additional Protocol I, Article 1(1) (adopted by 87 votes in favour, one against and 11 abstentions) (ibid., § 2).
[3] Additional Protocol I, Article 89 (adopted by 50 votes in favour, 3 against and 40 abstentions) (ibid., § 3).
[4] Second Protocol to the Hague Convention for the Protection of Cultural Property, Article 31, which states that “in situations of serious violations of this Protocol, the Parties undertake to act, jointly through the Committee, or individually, in cooperation with UNESCO and the United Nations and in conformity with the Charter of the United Nations”.
[5] Jean S. Pictet (ed.), Commentary on the Third Geneva Convention, ICRC, Geneva, 1960, p. 18; Yves Sandoz, Christophe Swinarski, Bruno Zimmermann (eds.), Commentary on the Additional Protocols, ICRC, Geneva, 1987, § 45.
[6] UN Security Council, Res. 681 (cited in Vol. II, Ch. 41, § 21).
[7] See UN General Assembly, Res. 32/91 A (ibid., § 22), Res. 37/123 A (ibid., § 23), Res. 38/180 A (ibid., § 24) and Res. 43/21 (ibid., § 25).
[8] See, e.g., Council of Europe, Parliamentary Assembly, Res. 823 (ibid., § 30), Res. 881 (ibid., § 31), Res. 921 (ibid., § 32) and Res. 948 (ibid., § 33); Council of Europe, Committee of Ministers, Declaration on the rape of women and children in the territory of former Yugoslavia (ibid., § 34); NATO, Parliamentary Assembly, Resolution of the Civilian Affairs Committee (ibid., § 35); OAU, Conference of African Ministers of Health, Res. 14 (V) (ibid., § 36); OAS, General Assembly, Res. 1408 (XXVI-O/96) (ibid., § 37).
[9] International Conference on Human Rights, Res. XXIII (ibid., § 38).
[10] International Conference for the Protection of War Victims, Final Declaration (ibid., § 43).
[11] Conference of High Contracting Parties to the Fourth Geneva Convention, Declaration (ibid., § 45).
[12] See ICRC, Conflict in Southern Africa: ICRC appeal (ibid., § 52), Conflict between Iraq and Iran: ICRC appeal (ibid., § 53), Conflict between Iran and Iraq: Second ICRC appeal (ibid., § 54) and Press Release No. 1498 (ibid., § 55).
[13] See, e.g., the statements of the United Kingdom (ibid., § 19) and United States (ibid., § 20).
[14] ICJ, Nicaragua case (Merits) (ibid., § 46).
[15] Draft Articles on State Responsibility, Article 16 (ibid., § 10).
[16] See, e.g., United States, Executive Office for Immigration Review and Board of Immigration Appeals, Medina case (ibid., § 14), in which the Board of Immigration Appeals found that it was unclear “what obligations, if any” common Article 1 was intended to impose with respect to violations of international humanitarian law by other States; United States, District Court for the Northern District of California, Baptist Churches case (ibid., § 15), in which the Court considered that common Article 1 was not a self-executing treaty provision because it did not “provide any intelligible guidelines for judicial enforcement” and did not prevent the United States from deporting persons to El Salvador and Guatemala; Canada, Federal Court Trial Division, Sinnappu case (ibid., § 13), in which the Court held that common Article 1 did not prevent Canada from returning unsuccessful refugee claimants to Sri Lanka.
[17] ICTY, Furundžija case, Judgment (ibid., § 47) and Kupreškić case, Judgment (ibid., § 48).
[18] For an overview of measures available to States to fulfil their obligation to ensure respect for international humanitarian law, see International Review of the Red Cross, No. 298, 1994, p. 9.
[19] Additional Protocol I, Article 89 (adopted by 50 votes in favour, 3 against and 40 abstentions) (cited in Vol. II, Ch. 41, § 3).