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Max Planck Encyclopedia of Public International Law [MPEPIL]

International Law, Development through International Organizations, Policies and Practice

Volker Röben

From: Oxford Public International Law (http://opil.ouplaw.com). (c) Oxford University Press, 2021. All Rights Reserved.date: 28 November 2021

Codification — Customary international law — General principles of international law — Soft law — Judicial decisions — Opinio juris — State practice

Published under the auspices of the Max Planck Institute for Comparative Public Law and International Law under the direction of Professor Anne Peters (2021–) and Professor Rüdiger Wolfrum (2004–2020). 

A.  Introduction

International organizations develop international law in a number of ways. All international organizations have the inherent and sometimes explicit power to pass rules, regulations, and other measures necessary for their internal operations. The more difficult question concerns the power of international organizations to develop international law that is externally binding (member States and/or third States). There is now a typology of instruments that international organizations regularly adopt that produce external legal effects and thus develop international law. These are partly but not wholly coextensive with the recognized sources of international law laid down in Art. 38 (1) ICJ Statute.

B.  Treaty-Making

As a matter of course, international organizations progressively develop international law through their involvement in the drafting of treaties. It is a prime function of most international organizations to provide the independent and neutral expertise that will identify the need for international law-making through treaties, to convene diplomatic conferences and shepherd the process of negotiating such treaties, inter alia, through administrative support, the provision of rules of procedure, to act as their depositary after conclusion, to follow-up on the wide ratification, and to ensure that they are effectively implemented.

A typical example of this role is the International Maritime Organization (IMO), whose mandate allows it to ‘provide for the drafting of conventions, agreements or other instruments and to recommend these to governments and to intergovernmental organizations and to convene such conferences as may be necessary’ (Art. 2 Convention on the Intergovernmental Maritime Consultative Organization [(done 6 March 1948, entered into force 17 March 1958) 289 UNTS 3]).

International organizations are, furthermore, capable of concluding treaties themselves with other international organizations or States to the extent they have treaty-making power (cf Art. 6 Vienna Convention on the Law of Treaties between States and International Organizations or between International Organizations; ‘VCLT-IO’; Treaty Making Power).

C.  Secondary Law-Making

As an alternative to traditional treaty-making, international organizations develop forms of regulation, conveniently, and as a matter of course in the European Union context, referred to as secondary (international) law (International Organizations or Institutions, Secondary Law), which is not treaty-law but which are acts adopted by an international organization pursuant to the powers conferred by that international organization’s constitutive instrument (the primary law). A typology of such secondary law comprises: a) abstract instruments of general application, b) administrative decisions, c) contractual-type arrangements, and d) judicial pronouncements, with e) general institutional law resulting from an inductive analysis of the primary and secondary law of international organizations.

1.  Abstract Instruments of General Application

(a)  Legislative-Type Instruments: The EU and the United Nations Security Council

International organizations adopt instruments of secondary legislation, understood as abstract rules of general application that become binding law per se without need or room for consent or ratification. The addressees of such legislation will usually be States. But it can also reach into the internal legal orders of States and directly confer rights and duties on individuals.

A prominent example is the EU, which has extensive powers to adopt secondary legislation in the form of so-called regulations and directives. While the former is binding in its entirety and directly applicable in the Member States (Art. 288 (2) Treaty on the Functioning of the European Union, [(signed 13 December 2007, entered into force 1 December 2009) (2008) OJ C115/1]; ‘TFEU’), the latter is binding as to the result to be achieved only (Art. 288 (2) TFEU). Individual treaty provisions provide the EU with defined powers and determine the procedure to be followed, which is now mostly the co-decision procedure requiring the Council of Ministers (through qualified majority voting) and the European Parliament to act in agreement. The parallel with domestic systems of legislation has been pushed even further by the Lisbon Treaty which provides for an ‘ordinary legislative procedure’ (Art. 294 TFEU).

Since the 1990s the UN Security Council has developed the practice of passing resolutions of a legislative-type structure. These resolutions set forth general provisions addressed to all Member States which need to take implementing action on which they report to a monitoring committee of the Security Council. The competence of the Council for such resolutions lies in Chapter VII, Arts 39 and 41 UN Charter, and possibly Art. 25 UN Charter. Art. 41 UN Charter empowers the Security Council to take any non-forcible measures it deems fit to maintain international security and world peace, including legislative-type action.

Such legislative-type resolutions have been passed by the Security Council in matters ranging from anti-terrorism (UNSC Res 1373 [2001] [28 September 2001]) to non-proliferation of weapons of mass destruction (UNSC Res 1540 [2004] [28 April 2004]).

10  This practice of the Security Council has received some criticism as being ultra vires or an abrogation of the treaty-making power pertaining to the Member States. However, the practice of the Security Council is arguably within its powers under Chapter VII UN Charter, and the UN Charter does not recognize any reserved competences for Member States other than Art. 2 (7) UN Charter which exempts Chapter VII powers of the Security Council.

(b)  Tacit Consent Procedures

11  International organizations that are UN agencies are regularly able to amend technical and other regulations of the treaties negotiated under their auspices or even the constitutive treaty to keep pace with the rapidly-evolving technology (tacit amendment; see also Treaties, Amendment and Revision). This means that the organization’s organ which adopts the amendment at the same time fixes a time period within which States Parties will have the opportunity to notify either their acceptance or their rejection of the amendment, or to remain silent on the subject. In case of silence, the amendment is legally considered to have been accepted by the party, unless the party has stated that its express approval is necessary. These amendments thus become binding on Member States without a further act of ratification or acceptance being required. Such regulatory authority need not be included in the constitutive treaty but may be conferred on the international organization by an implementing treaty or by decision of the organization’s plenary body.

12  Examples of such tacit amendments, effectively requiring States to opt out rather than to opt in as would be consistent with State consent, are the procedures of the IMO (eg Art. 16 International Convention for the Prevention of Pollution from Ships [(signed 2 November 1973, entered into force 2 October 1983) 1340 UNTS 184; ‘MARPOL Convention’]; Art. 8 International Convention for the Safety of Life at Sea, 1974 [(concluded 1 November 1974, entered into force 25 May 1980) 1184 UNTS 2]); the International Telecommunications Union (‘ITU’; Art. 54 Constitution and Convention of the International Telecommunication Union [(concluded 22 December 1992, entered into force 1 July 1994) 1825 UNTS 143]); the International Civil Aviation Organization (ICAO) (Art. 90 Convention on International Civil Aviation [(signed 7 December 1944, entered into force 4 April 1947) 15 UNTS 295]; ‘Chicago Convention’); the World Meteorological Organization (WMO) (Art. 28 Convention of the World Meteorological Organization [done 11 October 1947, entered into force 23 March 1950 1434 UNTS 3]); and the World Health Organization (WHO) (Arts. 21–2 Constitution of the World Health Organization [(signed 22 July 1946, entered into force 7 April 1948) 14 UNTS 185], Art. 59 World Health Organization ‘International Health Regulations’ [(adopted 23 May 2005, entered into force 15 June 2007) WHA58.3]); and also of regional fisheries organizations (Art. 12 North-East Atlantic Fisheries Convention [with Annex] [(signed 24 January 1959, entered into force 27 June 1963) 486 UNTS 157]). Similarly, the International Atomic Energy Agency (IAEA) may adopt safety standards that become binding in all operations in which the IAEA participates (Arts 3, 12 Statute of the International Atomic Energy Agency [(done 26 October 1956, entered into force 29 July 1957) 276 UNTS 4]). In the case of the ICAO, amendments (annexes) adopted by 2/3 majority in the Council become binding on all contracting States unless a majority of them registers their disapproval.

(c)  Administrative Rule-Making

13  A sub-category of abstract instruments comprises what may be labelled administrative rule-making. In contradistinction from secondary legislation such rule-making is not addressed to States or individuals in general, but governs an international organization’s administration of a given matter.

14  An example of such rule-making is provided by the International Seabed Authority (ISA) administering the exploration and exploitation of the mineral resources of the deep seabed pursuant to its regulations (Arts 160, 158 UN Convention on the Law of the Sea [done 10 December 1982, entered into force 16 November 1994] 1834 UNTS 397). Furthermore, the practice of international territorial administration developed by the UN in instances such as Kosovo and East Timor involves much rule-making applicable across the administered territory.

(d)  External Referencing

15  International organizations develop international law through acts that reference external instruments of general application produced by other actors that are not legally binding in themselves. The rationale is that the external actor has the expertise to flesh out provisions of the constitutive instrument of the international organization. The precise legal effect thus conferred on the external instrument needs to be assessed on a case-by-case basis. It may range from the legally binding incorporation of external standards to urging States to sign international conventions. This referential law-making will often fall within the mandate of an international organization whose purposes normally include inter-institutional co-operation (see also cooperation, International Law of).

16  Examples are the World Trade Organization’s Appellate Body referencing the standards of the Codex Alimentarius Commission (CAC) on the basis of Art. 4 Agreement on the Application of Sanitary and Phytosanitary Measures ([signed 15 April 1994, entered into force 1 January 1995] 1867 UNTS 493; ‘SPS Agreement’; World Trade Organization EC—Trade Description of Sardines: Report of the Appellate Body [26 September 2002] WT/DS231/AB/R) and UN Security Council Chapter VII resolutions referencing resolutions of the IAEA (eg UNSC Res 1874 [2009] [22 June 2009] UN Doc S/RES/1874 [2009]).

17  A reverse-type of referencing takes place where (non-binding) instruments such as standards and guidelines or even conventions adopted by international organizations are referenced by an international treaty and thereby conferred upon binding legal effect. A prime example is Art. 211 UN Convention on the Law of the Sea, implicitly referencing conventions and arguably certain standards adopted by IMO (Art. 211 UN Convention on the Law of the Sea). The referenced external standards of an international organization may also be set out explicitly by treaty. This static type of referencing is employed by the MARPOL Convention 73/78, whose Annex II Regulation 13 incorporates a specific IMO code.

(e)  Decision-Making Procedures

18  The procedure to be followed by the international organization in adopting any of the above normative instruments may variously call for unanimity, consensus, or different types of majority voting and qualified majority voting, meaning not just a simple or absolute majority but the stipulation of a quorum and the weighting of members’ votes in accordance with the functions of the international organization. Art. 27 (3) UN Charter according to which decisions of the UN Security Council on non-procedural matters are to be made by affirmative vote of nine members, including the concurring votes of the permanent members, is a well-known example of such qualified majority voting (for further examples see Sands and Klein 275–81).

19  There is also decision-making on normative instruments by limited membership bodies (eg ICAO Council, ISA Council); representation in these bodies will be based on the principles of: a) equitable geographical distribution, b) interests affected in the case of the UN specialized agencies and ISA, and c) weighting of the votes of Member States in the case of economic organizations.

20  The combination of majority voting and decision-making by limited membership bodies comes close to meeting a comprehensive concept of legislation, referring to abstract norms of general application, susceptible of repeated application, which may be adopted by majority vote but become binding on the minority (International Organizations or Institutions, Decision-Making Process; see also International Organizations or Institutions, Decision-Making Bodies).

2.  Administrative Decisions

21  International organizations also develop international law through their power to take administrative-type action, applying law in specific instances. The authority vested in international organizations to take administrative decisions varies widely in form and legal effect.

22  The most elaborate examples are the EU Commission’s power to adopt binding decisions (Art. 288 (4) TFEU) to administer, inter alia, the areas of competition and State aid (see also European Administrative Law), and the International Seabed Authority’s power to administer the deep seabed through binding decisions (Art. 162 UNCLOS).

3.  Contractual-Type Arrangements

23  Contractual-type arrangements entered into by international organizations and States consistent with the international organizations’ mandates further develop international law in two respects. They will not only create specific contractual-type rights and obligations for the parties to the arrangement, but they will also often reference instruments and policies thus conferring legal authority on them.

24  The World Bank is a leading exponent of this practice, in concluding legally binding loan agreements with borrowers (the recipient State) under international law registered with the UN, which include the Bank’s policies and sometimes also external instruments.

4.  Judicial and Quasi-Judicial Pronouncements

25  Increasingly, international organizations provide courts or tribunals with compulsory jurisdiction over disputes between the organization and its Member States, its staff, or even individuals, and sometimes also over disputes between Member States (Administrative Boards, Commissions and Tribunals in International Organizations). Organizationally, such courts or tribunals may be either attached to an existing international organization or be set up as a separate international organization. Similar dispute resolution functions may be exercised by internal oversight bodies that are institutionally shielded from the international organization.

26  In accordance with their compulsory jurisdiction, the courts and tribunals hand down judicial decisions that become binding on the parties to the dispute without their consent.

27  The legal precedent effect of such pronouncements regularly transcends the dispute at issue, raising the spectre of the relationship with the International Court of Justice (ICJ) and its universal but not compulsory jurisdiction.

28  Examples are the EU court system that has all the heads of jurisdiction mentioned, the International Tribunal for the Law of the Sea (ITLOS) (which is an international organization) with jurisdiction over disputes, the International Seabed Authority and individual operators, and between States parties to the UN Convention on the Law of the Sea, the UN Staff Tribunal with jurisdiction over disputes with staff, the World Trade Organization (WTO) Panels and Appellate Body (regardless of whether they can be classified as courts in the full sense) with jurisdiction over disputes between member States, the World Bank’s International Centre for Settlement of Investment Disputes (ICSID) with jurisdiction over disputes between parties to the Centre’s foundational treaty, and the World Bank’s Inspection Panel with administrative review jurisdiction over disputes between the Bank and affected individuals.

29  In addition, there are quasi-judicial pronouncements made by specialized organs of international organizations in the course of controlling compliance with and enforcing obligations of Member States under the constitutive instrument, an example of which is the UN Human Rights Council.

5.  International Institutional Law

30  From international organizations’ constitutive instruments and the internal and external secondary international law developed through the practice of international organizations, a ‘general part’ of the law of international organizations (also international institutional law or international administrative law) can be analytically deduced. The function of this body of principles and rules is to ensure that (legal) rationality is observed in the exercise of international law-development powers by international organizations. It covers, inter alia, a typology of legal instruments, procedures, legality requirements, enforcement, and judicial review. It is applicable to all or almost all subject-matter-specific international law developed by international organizations.

D.  General International Law

31  International organizations also contribute to the development of norms of general international law, understood as comprising customary international law and certain principles of international law.

1.  Customary International Law

32  Customary law in this age uses institutionalized shortcuts, including reliance on UN General Assembly resolutions. Thus, customary international law also becomes the product of the input of international organizations’ organs claiming universal participation (plenary bodies), neutral status or expertise (secretariats, and international courts, independent expert bodies), and affecting, reflecting, or substituting State practice and opinio iuris within the meaning of Art. 38 (b) ICJ Statute.

(a)  UN General Assembly Resolutions

33  An important instance of customary international law development by acts of international organizations is constituted by certain resolutions of the UN General Assembly. Two types of resolutions need to be distinguished in this regard.

34  A first group comprises resolutions such as the UNGA Res 217 A (III) ‘Universal Declaration of Human Rights’ ([10 December 1948] GAOR 3rd Session Part I Resolutions 71) and the UNGA Res 2625 (XXV) ‘Declaration on Principles of International Law concerning Friendly Relations and Co-operation among States in Accordance with the Charter of the United Nations’ ([24 October 1970] GAOR 25th Session Supp 28, 121) that set forth legally operable provisions. Such resolutions do not constitute law per se but they can crystallize into law by constituting evidence of the opinio iuris requirement of customary international law (Military and Paramilitary Activities in and against Nicaragua [Nicaragua v United States of America] [Merits] [1986] ICJ Rep 14); may be declaratory of customary international law (Armed Activities on the Territory of the Congo [Democratic Republic of the Congo v Uganda] [(2005) ICJ Rep 168] para. 162); and, according to some, may even come to be seen as authentic interpretations of relevant parts of the UN Charter.

35  A second group of resolutions contains statements on broad principles such as the common heritage of mankind and the responsibility to protect. While again not constituting law in themselves, certain legal effects accrue to such GA pronouncements. Among these effects is the provision of internal consistency and coherence to a body of law, of criteria for distinguishing several areas of international law, and of guidance for the progressive development of the field concerned.

(b)  Expert Bodies

36  Other institutionalized work products restate the existing customary international law, prime examples of which are the ‘Draft Articles on State Responsibility’ ([1996] GAOR 51st Session Supp 10, 125) produced by the International Law Commission (ILC).

2.  Principles of International Law

37  The practice of international organizations also makes a contribution to the development of those existing principles that provide the substantive underpinnings, if not the order, of international law (cf Dahm Delbrück and Wolfrum). Among these are territorial integrity (see also Territorial Integrity and Political Independence), non-intervention, prohibition of the use of force (Use of Force, Prohibition of), and self-determination. By virtue of their legal structure, such principles will often require interpretation and balancing with others. Practice of international organizations competent to pronounce on the principles which produces generalizable rules as a result of such interpretation will be relevant in future cases requiring interpretation and application of the principles concerned.

38  An example of this type of development of international law by international organizations is UNSC Res 1244 (1999) ([10 June 1999] SCOR 54th Year 32), which, in the instance of Kosovo, balances the principles of territorial integrity and self-determination of peoples by setting forth an obligation for all parties involved to enter into negotiations with the objective of reaching a peaceful solution to Kosovo’s status. A similar instance is the interpretation of the universal human rights standard by the UN Human Rights Council as part of its universal periodic review procedure.

E.  Non-Binding Instruments (‘Soft Law’)

39  The capacity to develop international law of the myriad forms of non-binding deontic instruments (recommendations, guidelines, codes of practices, etc), sometimes referred to as soft law, that many international organizations are empowered to produce cannot be assessed using a single template. At least six hypotheses need to be distinguished: such ‘soft law’ may serve as a starting point for the development of secondary law by international organizations, it may be incorporated by reference, it may crystallize into customary law, and it may be resorted to in the interpretation of existing law (Interpretation in International Law) including the constitutive treaties of international organizations (eg the ‘Guidelines on Conditionality’ [25 September 2002] interpreting Art. 5 (3) Articles of Agreement and Surveillance under its Art. 4, adopted as decisions of the International Monetary Fund [IMF] executive directors). Furthermore, States may consider standards adopted by an international organization as a benchmark for national legislation either because of an international obligation (cf Art. 12 Chicago Convention) or because of the standards’ intrinsic value (eg the Basel Concordat and the Basel Accords of the Basel Committee of the Bank for International Settlements).

F.  Enumerated Competences, Interpretative Principles, and Judicial Review

40  Most constitutive instruments for international organizations explicitly or implicitly embody the principle of enumerated competences for the organization. The upshot of this principle is that the international organization needs to stay within the powers conferred by the constitutive instrument, which need not be a treaty, or other rules of the organization (intra vires), and consequently that ultra vires acts are invalid and void (cf Art. 69 VCLT-IO). While it is generally difficult to draw the exact line between interpretation and the progressive development of any legal instrument (Codification and Progressive Development of International Law), this is particularly so regarding the constitutive documents of international organizations. Accepted interpretation techniques for such documents include the doctrines of implied powers (for internal matters; International Organizations or Institutions, Implied Powers) and of effectiveness (effet utile), which tend to amplify the powers of the international organizations, complemented by the possibility of ad hoc authentic interpretation and its derivatives by Member States. A ‘constitutional’ interpretation working in analogy with domestic constitutional law may be acceptable in certain instances. The proper interpretive approach including the use of the said doctrines must be specific to the respective organization and its context.

41  Judicial control of international organizations’ law-development against this standard can be exercised by courts and tribunals to the extent that they have contentious or—practically important—advisory jurisdiction over the acts of the organization. The ICJ’s Certain Expenses of the United Nations (Advisory Opinion) (at 167) may be seen as establishing a presumption of legality, which is rebuttable in obvious circumstances (see Legality of the Use by a State of Nuclear Weapons in Armed Conflict [Advisory Opinion] ;Constitution of the Maritime Safety Committee of the Intergovernmental Maritime Consultative Organization [Advisory Opinion] 159). Additionally, ius cogens (Art. 53 VCLT-IO) may be a yardstick against which to measure acts of international organizations. Finally, the acts of an international organization may be subject to judicial control against fundamental legal standards including human rights of another international organization (cf Joined Cases C-402/05P and C-415/05P Kadi v Council of the European Union [(2008) ECR I-6351]), or even against the constitutional law of individual Member States (cf 2 BvE 2/08 Bundesverfassungsgericht [German Federal Constitutional Court 2nd Senate] [30 June 2009]).

G.  Outlook

42  It can safely be predicted that the practice and supporting policies of international organizations developing international law will further expand in the future, regardless of the somewhat unclear theoretical foundations of this practice (see Klabbers 184–88: distinguishing treaty-analogy, delegation, and legislation theories). The crucial legal criterion is the requirement of acting in conformity with the enumerated competences of the organization set forth in the constitutive instrument, and arguably also with fundamental human rights standards, ius cogens, and the emerging international institutional law. This is mainly a matter of treaty interpretation. This intra vires requirement becomes the more relevant normatively the more international organizations embrace forms of regulation that approximate the law of the administrative State. In addition, in considering its potential law-developing practice an international organization needs to be conscious of its legitimacy, major determinants of which are its representativeness, its accountability, and the transparency of its operations.

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