B. Background

4. In the past half-century, the scope of international law has increased dramatically. From

a tool dedicated to the regulation of formal diplomacy, it has expanded to deal with the most

varied kinds of international activity, from trade to environmental protection, from human rights

to scientific and technological cooperation. New multilateral institutions, regional and universal,

have been set up in the fields of commerce, culture, security, development and so on. It is

difficult to imagine today a sphere of social activity that would not be subject to some type of

international legal regulation.

5. However, this expansion has taken place in an uncoordinated fashion, within specific

regional or functional groups of States. Focus has been on solving specific problems rather than

attaining general, law-like regulation. This reflects what sociologists have called “functional

differentiation”, the increasing specialization of parts of society and the related autonomization

of those parts. It is a well-known paradox of globalization that while it has led to increasing

uniformization of social life around the world, it has also led to its increasing fragmentation -

that is, to the emergence of specialized and relatively autonomous spheres of social action and

structure.

6. The fragmentation of the international social world receives legal significance as it has

been accompanied by the emergence of specialized and (relatively) autonomous rules or

rule-complexes, legal institutions and spheres of legal practice. What once appeared to be

governed by “general international law” has become the field of operation for such specialist

4 The following members participated in the work of the Study Group during the 2006 session:

Mr. M. Koskenniemi (Chair), Mr. A. Al-Marri, Mr. C. Chee, Mr. P. Comissario Afonso,

Mr. R. Daoudi, Mr. C.P. Economides, Ms. P. Escarameia, Mr. G. Gaja, Mr. Z. Galicki,

Mr. R.A. Kolodkin, Mr. W. Mansfield, Mr. M. Matheson, Mr. P.S. Rao, Ms. H. Xue.

A/CN.4/L.702

page 4

systems as “trade law”, “human rights law”, “environmental law”, “law of the sea”, “European

law” and even such highly specialized forms of knowledge as “investment law” or “international

refugee law”, etc. - each possessing their own principles and institutions.

7. While the reality and importance of fragmentation cannot be doubted, assessments of

the phenomenon have varied. Some commentators have been highly critical of what they have

seen as the erosion of general international law, emergence of conflicting jurisprudence,

forum-shopping and loss of legal security. Others have seen here a predominantly technical

problem that has emerged naturally with the increase of international legal activity and may be

controlled by the use of technical streamlining and coordination. 5 It is in order to assess the

significance of the problem of fragmentation and, possibly, to suggest ways and means of

dealing with it, that the Commission in 2002 established the Study Group to deal with the matter.

8. At the outset, the Commission recognized that fragmentation raises both institutional and

substantive problems. The former have to do with the jurisdiction and competence of various

institutions applying international legal rules and their hierarchical relations inter se. The

5 “Fragmentation” is a very frequently treated topic of academic writings and conferences today.

Out of the various collections that discuss the diversification of the sources of international

regulation particularly useful are Eric Loquin & Catherine Kessedjian (eds.), La mondialisation

du droit (Paris: Litec, 2000); and Paul Schiff Berman, The Globalization of International

Law (Aldershot: Ashgate, 2005). The activity of traditional organizations is examined in

Jose Alvarez, International Organizations as Law-Makers (Oxford: Oxford University

Press, 2005). Different perspectives of non-treaty law-making today are also presented in

Rudiger Wolfrum & Volker Roben (eds.), Developments of International Law in Treaty-making

(Berlin: Springer, 2005) pp. 417-586 and Ronnie Lipschutz & Cathleen Vogel, “Regulation for

the Rest of Us? Global Civil Society and the Privatization of Transnational Regulation”, in

R.R. Hall & T.J. Bierstaker, The Emergence of Private Authority in Global Governance

(Cambridge: Cambridge University Press, 2002) pp. 115-140. See also “Symposium:

The Proliferation of International Tribunals: Piecing together the Puzzle”, New York Journal

of International Law and Politics, vol. 31 (1999) pp. 679-993; Andreas Zimmermann &

Reiner Hoffmann, with assisting editor Hanna Goeters, Unity and Diversity of International

Law (Berlin: Duncker & Humblot, 2006); Karel Wellens & Rosario Huesa Vinaixa (eds.),

L’influence des sources sur l’unite et la fragmentation du droit international (Brussels:

Bruylant, 2006 forthcoming). A strong plea for unity is contained in Pierre Marie Dupuy,

“L’unite de l’ordre juridique internationale. Cours general de droit international public”, Recueil

des Cours …, vol. 297 (2002). For more references, see Martti Koskenniemi & Paivi Leino,

“Fragmentation of International Law. Postmodern Anxieties? ”, Leiden Journal of International

Law, vol. 15 (2002) pp. 553-579.

A/CN.4/L.702

page 5

Commission has decided to leave this question aside. The issue of institutional competencies is

best dealt with by the institutions themselves. The Commission has instead wished to focus on

the substantive question - the splitting up of the law into highly specialized “boxes” that claim

relative autonomy from each other and from the general law. What are the substantive effects

of specialization? How should the relationship between such “boxes” be conceived? More

concretely, if the rules in two or more regimes conflict, what can be done about such conflicts?

9. Like the majority of academic commentators, the Commission has understood the subject

to have both positive and negative sides, as attested to by its reformulation of the title of the

topic: “Fragmentation of international law: difficulties arising from the diversification and

expansion of international law”. On the one hand, fragmentation does create the danger of

conflicting and incompatible rules, principles, rule-systems and institutional practices. On

the other hand, it reflects the expansion of international legal activity into new fields and the

attendant diversification of its objects and techniques. Fragmentation and diversification account

for the development and expansion of international law in response to the demands of a

pluralistic world. At the same time, it may occasionally create conflicts between rules and

regimes in a way that might undermine their effective implementation. Although fragmentation

may create problems, they are neither altogether new nor of such nature that they could not be

dealt with through techniques international lawyers have used to deal with the normative

conflicts that may have arisen in the past.

10. The rationale for the Commission’s treatment of fragmentation is that the emergence

of new and special types of law, so-called “self-contained regimes” and geographically or

functionally limited treaty-systems, creates problems of coherence in international law. New

types of specialized law do not emerge accidentally but seek to respond to new technical and

functional requirements. The emergence of “environmental law”, for example, is a response to

growing concern over the state of the international environment. “Trade law” develops as an

instrument to respond to opportunities created by comparative advantage in international

economic relations. “Human rights law” aims to protect the interests of individuals and

“international criminal law” gives legal expression to the “fight against impunity”. Each

rule-complex or “regime” comes with its own principles, its own form of expertise and its own

“ethos”, not necessarily identical to the ethos of neighbouring specialization. “Trade law” and

“environmental law”, for example, have highly specific objectives and rely on principles that

A/CN.4/L.702

page 6

may often point in different directions. In order for the new law to be efficient, it often includes

new types of treaty clauses or practices that may not be compatible with old general law or the

law of some other specialized branch. Very often new rules or regimes develop precisely in

order to deviate from what was earlier provided by the general law. When such deviations

become general and frequent, the unity of the law suffers.

11. It is quite important to note that such deviations do not emerge as legal-technical

“mistakes”. They reflect the differing pursuits and preferences of actors in a pluralistic (global)

society. A law that would fail to articulate the experienced differences between the interests or

values that appear relevant in particular situations or problem areas would seem altogether

unacceptable. But if fragmentation is a “natural” development (indeed, international law was

always relatively “fragmented” due to the diversity of national legal systems that participated

in it), there have likewise always been countervailing, equally natural processes leading in the

opposite direction. For example, general international law has continued to develop through the

application of the Vienna Convention on the Law of Treaties of 1969 (VCLT), customary law

and “general principles of law recognized by civilized nations”. The fact that a number of

treaties reflect rules of general international law, and in turn, certain provisions of treaties enter

into the corpus of general international law, is a reflection of the vitality and synergy of the

system and the pull for coherence in the law itself.

12. The justification for the Commission’s work on fragmentation has been in the fact that

although fragmentation is inevitable, it is desirable to have a framework through which it may be

assessed and managed in a legal-professional way. That framework is provided by the VCLT.

One aspect that unites practically all of the new regimes (and certainly all of the most important

ones) is that they claim binding force from and are understood by the relevant actors to be

covered by the law of treaties. This means that the VCLT already provides a unifying frame for

these developments. As the organ that once prepared the VCLT, the Commission is in a

privileged position to analyse international law’s fragmentation from that perspective.

13. In order to do that, the Commission’s Study Group held it useful to have regard to

the wealth of techniques in the traditional law for dealing with tensions or conflicts between

legal rules and principles. What is common to these techniques is that they seek to establish

A/CN.4/L.702

page 7

meaningful relationships between such rules and principles so as to determine how they should

be used in any particular dispute or conflict. The following conclusions lay out some of the

principles that should be taken account of when dealing with actual or potential conflicts

between legal rules and principles.