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C. The creation of customary law

So far this chapter has dealt almost exclusively with international legislation through the multilateral treaty-making process, which indeed is the principal method of manufacturing new international law.

However, as already mentioned in the introduction, customary law is the other main source of rights and obligations under international law and therefore cannot be entirely neglected in the present context. This is especially so because customary, unlike conventional, law generally applies to all states (except those that have always and consistently excluded themselves from the practice in question) and not only to the parties to a particular instrument.

At first sight, it seems oxymoronic to suggest that customary law which is derived inductively from the practice of states insofar as such practice is motivated by a sense of legal obligation - can be "legislated" in the usual sense of that term. And, of course there is no straightforward way of doing so, comparable to the treaty route, which though long and tortuous, can be seen as proceeding step by step from the proposal to initiate to the entry into force of a multilateral law-making treaty.

Nevertheless, customary law can be somewhat shaped and directed, because the practices of states can be consciously affected by various international actions, particularly by significant IGOs. Many of the hundreds of resolutions that are adopted each year by international organs are addressed to states and recommend that they act in particular ways and may even suggest that they are legally obliged to do so - obviously in the hope, if not the firm expectation, that some or many will conform their conduct as a result of these importunings.

Although most such recommendations are expressed in ordinary resolutions and deal with issues of lesser or transitory moment, some are deliberately framed as solemn or universal declarations and adopted with ceremony by a senior organ, such as the United Nations General Assembly. The expectation that states will make a real effort to conform their conduct to such texts appears from their preambles or from the adopting resolutions, and sometimes also from later inquiries, usually solicited by the adopting organ and addressed to the executive head of the IGO, as to how states have actually responded to the declaration.

The formulation of such a declaration is often subject to essentially the same procedures as described in respect of multilateral treaties, involving consideration by expert and representative organs, consultations with governments and with NGOs, and adoption in a plenary organ by a high majority or by consensus.47 Indeed sometimes when this process is started it may not be clear whether the final product will be a declaration or a treaty, and the choice between these two may only be made at a relatively advanced stage of the process that is, when it can be determined if at that stage a sufficient number of states is prepared to enter into a binding treaty. But, whether or not a declaration is originally adopted only as a second-best solution, it may then serve as the forerunner of a later treaty, in that the groundwork is laid and the general legal principle is established by the former instrument, while the later treaty covers the same lines, though in greater detail and with more precision.

Solemn legislative declarations48 can thus contribute to the international legislative process in two entirely separate ways. They may be precursive to and guide a later treaty-making process, in which reference is often made to the general legal principle already stated in the declarations.49 And they are also and perhaps primarily designed to influence the conduct of states directly -and to the extent that they are successful in doing so international customary law may be created. In effect they may catalyse the creation of customary law by expressing in normative terms certain principles whose general acceptance is already in the air (for otherwise their adoption by an IGO organ would not receive the necessary support) and thereby making it easier and more likely for states to conform their conduct to them.

There is yet another and in a sense more circuitous way in which the creation of new customary law can be furthered through deliberate international action: i.e. through the adoption of multilateral lawmaking treaties. Though of course these instruments primarily create rights and obligations only for their parties and thereby influence their conduct, to the extent that such conduct then becomes the international standard, even states that for some reason have not become parties to the treaty may feel obliged to conform their conduct to some or all of the treaty provisions.50 Thus the process of creating new law-making treaties may, as a by-product, also facilitate the creation of new customary law.

This having been said, it must also be admitted that so far there are few clear instances of customary environmental legal principles. This is largely so because environmental law itself is of relatively recent vintage, and thus there has been little time for consistent state practice to develop, either in response to solemn declarations by IGOs or through the general acceptance of norms set out in multilateral treaties.51 However, the processes described above have in other areas, and in particular that of human rights, been notably productive in the creation of customary law, and there is therefore every reason to expect that the same will apply in respect of environmental principles.

D. The creation of soft law

Both conventional and customary rules are binding, or "hard" law in a sense, the only type of international law that properly deserves that designation.52 However, in recent times another type of international law has more and more come to be recognized, that is non binding, or "soft," law. What that term describes are numerous norms that are in effect observed by states even though, strictly speaking, they are not obliged to do so; however, the fact that they are generally observed, and are expected to be so, gives them a predictive value similar to those norms expressed in hard law - which of course is also not always observed.

Generally a norm may be "soft" when it either does not constitute part of a binding regime, whether of conventional or customary law, or because, even though it is contained in a binding instrument' it is not expressed in obligatory language. In environmental regimes, examples of both types of soft law abound, and most are ones created by IGOs.

As already pointed out, many important environmental principles are merely set out in resolutions or other decisions of IGO organs that, with few exceptions, are not binding per se. This is true, for example, of the Principles set out in the Stockholm Declaration and of the paragraphs of the World Charter for Nature, except insofar as these may either merely restate pre-existing rules of customary international law53 or may have become such by the mechanisms discussed in the previous section.54 Possibly even more significant because more numerous and practical are the many "guidelines," "principles," or recommended practices adopted by or under the authority of IGO organs, such as the UNEP Governing Council55 or other corresponding bodies, and largely followed by states.

With respect to the second type of soft law described above, many multilateral treaties negotiated under the aegis of lGOs contain clauses that are not intended to create firm obligations - evidently because the prospective parties were not, at least at the time, willing to bind themselves as to these points. This is particularly true of the framework or umbrella agreements, the substantive provisions of which tend to be merely hortatory or programmatic,56 while the ultimately effective dispositions are the procedural ones pursuant to which subsidiary instruments with binding substantive obligations are formulated and adopted.

Why, if soft law norms are not binding, are they in fact observed? There are indeed several reasons. One is that if a particular norm is negotiated within an IGO and then included either in a non-binding declaration or in a non-obligatory form in a treaty, the states concerned are generally desirous or at least content to observe it - for otherwise they would not have adopted it at all; thus the very fact that the norm has been articulated, usually by consensus, suggests that even if at that stage governments were not willing to bind themselves (perhaps because they first wished to observe the consequences of actual implementation), in practice they would normally follow it. Another reason for observance might be that the IGO concerned through some mechanism or other follows up on implementation of the norms it has promulgated; such follow-up may consist of no more than periodic reminders of the importance of faithful observance,57 to arrangements for receiving reports on compliance, which the IGO may then discuss in an expert or a representative organ - i.e. the "mobilization of shame." Finally, in some instances certain states particularly interested in the observance of a non-binding norm may unilaterally exert effective pressure for compliance by other states.58

In evaluating the importance of soft law, account must also be taken of the various ways in which it may, often quite rapidly, be hardened. One way of course is the incorporation of an initially non-binding norm into a binding treaty - which, for example, is the normal and expected course when a general framework convention is supplemented by binding protocols. Another is the creation of customary law when states adopt as their practice, acting out of a combination of a sense of legal obligation and in response to some of the pressures described above, rules that originally were merely expressed in solemn (but nevertheless non-binding) declarations.

All in all, in considering how IGOs actually influence the action of states in the environmental field, it is important to take account of the large number of at least initially non-binding norms that are formulated and promulgated in various forms by these organizations.

E. Concluding remarks

The international legislative process is productive and capable of expressing as international law whatever rules and regimes the world or the appropriate special or regional community can agree on. Such law is most conveniently set out in the form of multilateral treaties applicable to the states that become parties, but may also take the form of less precise but generally applicable customary law stimulated and crystallized by the systematic adoption of formal declarations and even as the by-product of widely accepted conventional rules: finally, certain norms may, at least initially, take the form of non-binding but still generally observed soft law.

The quality of the international environmental rules thus established depends in the first instance on the expertise of the specialized representative, expert, and secretariat organs charged with carrying out or assisting these legislative tasks, which for the most part are likely to be the organs of a number of existing IGOs active in this field. Such organs are already quite numerous in the UN system and in some of the major regional agencies, though it may be useful to establish some even more technically specialized organizations and organs, for example such as might be required to deal with the threats of global climatic changes or to protect certain international commons from pollution. The establishment of such organizations and organs of course itself requires and is also part of the international legislative process.

The great weakness of that process, i.e. the considerable unevenness in the applicability of even carefully formulated conventional law, due in part to reservations and options but largely to the quantitative and technical incapability of many states to deal with the increasing flow of international legislation, should be recognized and countered by effective measures to assist states, particularly the developing ones, in becoming parties to and in absorbing into their domestic legal systems the considerable body of existing conventional environmental law, and then to perform the same service in respect of later additions to the canon.

Because of the great expertise, energy, and sometimes the material resources of national and international environmental NGOs, these should be encouraged and permitted to participate as far as possible in all aspects of the relevant international legislative process: the studies required to decide whether to initiate the process in respect of a particular problem; the formulation of instruments designed to deal with that problem; the adoption of such instruments by competent international bodies; and finally the rapid ratification of such instruments by as many as possible of the potential parties thereto. Such encouragement will also make the process more responsive than most international actions to the aspirations and concerns of the world's people.

It has been pointed out that the international legislative process is anything but too rigid; indeed, its formlessness and flexibility may be disturbing to some who, used to well-established but narrowly constrained municipal procedures, consider anything so variegated as multilateral treaty-making to constitute not really a "process" but at best unstructured diplomatic interactions that may fortuitously result in some useful codification or progressive development of international law but cannot really be relied on to do so. Actually, however, while an overall survey of the process may, at least at first sight, be confusing because of its manifold manifestations, certain specialized law-making units have over the years evolved rather precise and predictable legislative methodologies, which those who are experienced can rely on and use. However, and generally speaking this should be deemed an advantage, with the possible exception of a few organizations and fore, the multilateral treaty-making process remains flexible enough so that it can be adapted to the needs of particular situations and proposed instruments. Moreover, being flexible, it can more easily adapt as improvements are suggested, either by the imagination of some of the participants or arising out of institutional experience or news of the experience of other similar bodies. In short, international institutions are basically young and can and do learn,59 and that learning generally - unless occasionally false lessons are absorbed results in improving the operations of these organizations.

There is another, perhaps more surprising, observation to make about international law-making. One might believe that in a process largely carried out by the instructed and to a considerable extent freely replaceable governmental representatives, there would not be much room for individual initiative or merit, or cause to assign individual credit - or blame - for the success or failure of a particular legislative enterprise. Such a conclusion, however, would be quite wrong. The international legislature ultimately consists of people who interact, often for many years, sometimes in respect of many political enterprises and sometimes predominantly in respect of one. This interaction breeds loyalties both to persons and more often to causes that may transcend a particular representative's instructions and especially the vaguely expressed directives that emanate from most governments in respect of international political enterprises far from home.60 There are therefore any number of examples of how a particular individual, or sometimes several, will decisively and essentially personally influence the formulation of a particular treaty. These persons more often than not are representatives of minor states (the major ones tending to control their delegates more closely) who through their merits (usually including a dose of longevity) capture key positions in developing some instrument: chair of an influential expert group, of a drafting committee, or of a more prominent body such as the formulating organ; indeed, often they work their way up, tending to a particular draft instrument in different and sometimes ever-more prominent roles over the years. Alternatively such persons may occupy leading positions (e.g. executive head) in the competent secretariat or unit. In other instances, strong support has come from rank outsiders, who are persistent and skilful in lobbying or pressuring governments or their representatives in some self-adopted cause on behalf of a public-spirited body. In any event, an instrument or project that attracts the support of one or more talented and dedicated legislative heroes, preferably from nominally opposite camps, is much more likely to succeed than can be predicted by a sober political analysis of the supposed interests of power blocks.


Chronology of principal development in international legislation concerning the atmosphere

A. Protection against transboundary air pollution1

1969 Eric Oden, studies on acidification of Scandinavian lakes by long-range air pollution
Jun. 1972 Swedish case-study on "Air Pollution Across National Boundaries: Impact on the Environment of Sulfur in Air and Precipitation" (submitted to the Stockholm Conference)
18 Jun. 1974 OECD Council Recommendation on Guidelines for Action to Reduce Emissions of Sulphur Oxides and Particulate Matters from Fuel Combustion in Stationary Sources
14 Nov. 1974 OECD Council Recommendation on Measures Required for Further Air Pollution Control
1 Aug. 1975 Helsinki Final Act of the Conference on Security and Co-operation in Europe (calling, inter alia, for promoting international law in respect of long-range air pollution)
1977 OECD study on lang-range transboundary air pollution in Europe
1978 Establishment of the Co-operative Programme for Monitoring and Evaluation of the Long Range Transmission of Air Pollutants in Europe (EMEP), by ECE in co-operation with WMO and UNEP
1978 Negotiation of a long-range transboundary air pollution convention within the framework of the Senior Advisers to ECE Governments on Environmental Problems
Jul. 1982 Ministerial Conference on Acidification, Stockholm
21 Mar. 1984 Ministerial Conference on Acid Rain, Ottawa
27 Jun. 1984 Multilateral Conference on Environment, Munich
Oct. 1985-Aug. 1988 Negotiation of a Protocol on Nitrogen Oxides
31 Oct. 1988 Declaration on 30 Per Cent Reduction of Nitrogen Oxide Emissions, Sofia
24 Nov. 1988 EEC Directive on the Limitation of Emissions ofCertain Pollutants in the Air from Large Combustion Plants
Feb. 1989- Negotiation of a Protocol on Volatile Organic
Aug. 1991 Compounds

1. Code:

Scientific Developments and Meetings Not Part of International Legislative Process

Legal and Political Meetings and Statements Not Part of Non-Regional International Legislative Process

Meetings Relating to the International Legislative Process

B. Protection of the ozone layer

1973-1974 Richard Stolarski and Ralph Cicerone, studies of release of chlorine in the atmosphere
1974 Mario Molina and Sherwood Rowland, studies of CFCs in the atmosphere and stratosphere
8 Mar. 1977 UNEP's World Plan of Action on the Ozone Layer, Washington
Apr. 1980 UNEP Governing Council resolution on restriction of CFC usage
May 1981 UNEP Governing Council resolution initiating negotiations towards an ozone agreement
1981 Meeting of legal experts convened by UNEP, Montevideo
Jan. 1982 First session of Ad Hoc Working Group of Legal and Technical Experts for the Preparation of a Global Framework Convention for the Protection of the Ozone Layer, convened by UNEP, Stockholm (NB: There were seven sessions, until 1985)
1983 Establishment of the "Toronto Group"
1986 WMO/UNEP Report on Atmospheric Ozone
May 1986 Workshop on CFC production and consumption trends, convened by EEC and UNEP, Rome
Sep. 1986 Workshop on alternative regulatory strategies on protection of ozone, convened by USA and UNEP, Leesburg (USA)
Dec. 1986 First negotiating session on a protocol to the Vienna Convention, convened by UNEP, Geneva
Feb. 1987 Second negotiating session on a protocol to the Vienna Convention, convened by UNEP, Vienna
Apr. 1987 Third negotiating session on a protocol to the Vienna Convention, convened by UNEP, Geneva
Jun. 1987 Meeting of heads of key delegations, convened by UNEP, Brussels
8-13 Sep. 1987 Preliminary meetings preceding the Montreal Conference, convened by UNEP, Montreal
Apr.- May 1989 First Meeting of the Parties to the Vienna Convention and the Montreal Protocol, Helsinki
27-29 Jun. 1990 Second Meeting of the Parties to the Vienna Convention and the Montreal Protocol, London (adoption of ADJUSTMENTS AND AMENDMENTS TO MONTREAL PROTOCOL)
Jun. 1991 Third Meeting of the Parties to the Vienna Convention and the Montreal Protocol, Nairobi (also Executive Committee of Interim Multilateral Fund)
Oct. 1992 Fourth Meeting of the Parties to the Vienna Convention and the Montreal Protocol, Copenhagen

C. Protection of the climate

12-23 Feb. 1979 First World Climate Conference, convened by WMO
9-15 Oct. 1985 International Conference on the Assessment of the Role of Carbon Dioxide and Other Green-house Gases in Climate Variations and Associated Impacts, Villach (Austria), sponsored by UNEP, WMO, and ICSU
28 Sep.- 2 Oct. 1986 Conference on Developing Policies for Responding to Future Climatic Change, Villach (Austria)
1986 Establishment of the UN system inter-agency Advisory Group on Greenhouse Gases (AGGE)
Nov. 1987 Policies Issues Workshop on Developing Policies for Responding to Climatic Change, Bellagio (Italy)
27-30 Jun. 1988 Conference on the Changing Atmosphere: Implications for Global Security, convened by the Canadian Department of External Affairs, Toronto
Nov. 1988 First session of the Intergovernmental Panel on Climate Change (IPCC), Geneva, established by UNEP and WMO
6 Dec. 1988 UNGA Resolution: Protection of Global Climate for Present and Future Generations of Mankind (A/RES/43/53)
20-22 Feb. 1989 Meeting of Legal and Policy Experts on the Changing Atmosphere, convened by the Canadian Department of External Affairs, Ottawa
11 Mar. 1989 Declaration of the Hague
28-30 Jun. 1989 Second session of IPCC, Nairobi
7 Nov. 1989 Noordwijk Declaration of the Ministerial Conference on Atmospheric Pollution and Climate Change
1990 Third session of IPCC
27-31 Aug. 1990 Fourth session of IPCC, Sundsvall (Sweden)
29 Oct.- 7 Nov. 1990 Second World Climate Conference, convened by WMO, Geneva, and Ministerial Declaration
21 Dec. 1990 Establishment of Intergovernmental Negotiating Committee for a Framework Convention on Climate Change (A/RES/45/212)
4-14 Feb. 1991 First session of the Intergovernmental Negotiating Committee for a Framework Convention on Climate Change, Washington
13-15 Mar. 1991 Fifth session of IPCC, Geneva
19-28 Jun. 1991 Second session of the Intergovernmental Negotiating Committee for a Framework Convention on Climate Change
9-20 Sep. 1991 Third session of the Intergovernmental Negotiating Committee for a Framework Convention on Climate Change
29-31 Oct. 1991 Sixth session of IPCC
9-20 Dec. 1991 Fourth session of the Intergovernmental Negotiating Committee for a Framework Convention on Climate Change
10-12 Feb. 1992 Seventh session of IPCC, Geneva
18-28 Feb. 1992 Fifth session of the Intergovernmental Negotiating Committee for a Framework Convention on Climate Change, New York
Apr. 1992 Informal consultations among principal delegations, Paris
30 Apr.- 8 May 1992 Sixth session of the Intergovernmental Negotiating Committee for a Framework Convention on Climate Change

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