FHS PUBLIC
INTERNATIONAL LAW
THE LAW OF TREATIES
Catherine Redgwell
Reader in Public International Law
St. Peter’s College
catherine.redgwell@spc.ox.ac.uk
BASIC READING
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1969 Vienna Convention on the Law of Treaties (VCLT)
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Harris, Cases and Materials on International Law (5th ed., 1998),
Ch. 10 or Dixon and McCorquodale, Cases and Materials on
International Law, (4th ed., 2003), Ch. 3
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Brownlie, Principles of Public International Law (6th ed., 2003), Ch.
XXV or Shaw, International Law (5th ed., 2003), Ch. 16 or Dixon,
Textbook on International Law (4th ed., 2000), Ch. 3
FURTHER REFERENCE
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*Aust, Modern Treaty Law and Practice (2000)
Jennings and Watts, Oppenheim's International Law (1992), Vol 1, Parts 2-4
Ch.14
*Sinclair, The Vienna Convention on the Law of Treaties (2nd ed., 1984)
* Reuter, Introduction to the Law of Treaties (2nd ed., 1995)
Rosenne, Developments in the Law of Treaties 1945-1986 (1989)
Klabbers, The Concept of Treaty in International Law (1996)
Klabbers and Lefeber, eds., Essays on the Law of Treaties (1998)
Multilateral Treaties Deposited with the Secretary General
2002 at http://untreaty.un.org
For a list of the current international agreements for which the UK is depositary,
see http://www.fco.gov.uk/directory/treaty.asp
LECTURE OUTLINE
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1. Introduction
2. Sources of the Law of Treaties
3. What is a Treaty?
4. Making Treaties: Conclusion and Entry into
Force
5. Reservations
6. Interpretation
7. Amendment and Modification
8. Grounds for Challenge
9. Termination
I. INTRODUCTION
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Treaties in modern international
relations
date modern treaty law from the
Congress of Vienna in 1815 where
there appeared for the first time “the
idea that a treaty which is binding upon
different States by the same terms
constitutes a single legal instrument”
(Reuter)
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multilateral treaty-making 1864-1914
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rise of international organisations and
their role
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League of Nations; United Nations role
as depositary and initiator of treatynegotiations (e.g. 1982 UN Convention
on the Law of the Sea)
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Treaties now an essential and
ubiquitous instrument in international
relations (Cf VCLT preamble)
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particular importance in fields such as
human rights (ICCPR), environmental
protection (FCCC; CBD), international
trade law (WTO/GATT)
• Enhanced support for rule of law:
• "[s]upport for the rule of law
would be enhanced if countries
signed and ratified international
treaties and conventions”
(Millennium Report (A/54/2000),
UN Secretary-General)
• Treaty signature/ratification
“events”
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Treaties as a source of international law
Article 38(1)(a) of the Statute of the ICJ
provides that in deciding in accordance
with international law such disputes as
are submitted to it, the Court shall
apply
"international
Conventions,
whether
general
or
particular,
establishing rules expressly recognised
by the contesting States.”
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"The order in which the sources of international law
are enumerated in the Statute of the International
Court of Justice is, essentially, in accordance both
with correct legal principle and with the character of
international law as a body of rules based on consent
to a degree higher than is law within the State. The
rights and duties of States are determined, in the first
instance, by their agreement as expressed in treaties
- just as, in the case of individuals their rights are
specifically determined by any contract which is
binding upon them. When a controversy arises
between two or more States with regard to a matter
regulated by a treaty, it is natural that the parties
should invoke and that the adjudicating agency
should apply, in the first instance, the provisions of
the treaty in question." (Lauterpacht, 1970)
TREATIES ON TREATIES
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1969 Vienna Convention on the Law of
Treaties (in force on 27 January 1980 and
presently has 94 Parties)
1978 Vienna Convention on Succession of
States in Respect of Treaties (in force 1996)
1986 Convention on the Law of Treaties
between
States
and
International
Organisations or between International
Organisations (not in force)
2. SOURCES OF THE LAW
OF TREATIES
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Scope of VCLT: covers traditional topics
but not exhaustive
VCLT: General Law or Progressive
Development?
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"A glance at the headings to the various Parts
of the Convention quickly reveals that it
covers all the topics traditionally regarded as
falling within the framework of the law of
treaties - that is to say, the conclusion and
entry into force of treaties (including
reservations), the observance, application and
interpretation of treaties, the amendment and
modification of treaties, and the invalidity,
termination and suspension of operation of
treaties. The Convention in addition lays
down
procedural
rules
concerning
depositaries, notifications, corrections and
registration." (Sinclair, 1984)
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Definition of treaty Art. 2(1)(a)
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only written agreements between States
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cil governs matters outwith VCLT
(preamble, 8th indent)
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What isn’t regulated? Chiefly effects of
war on treaties; succession (1986
treaty); state responsibility (cf. Pt. 9,
Gabicikovo-Nagymaros Dam Dispute)
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Article 3 VCLT (exclusions)
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Article 5 VCLT: constituent instruments
are covered (e.g. UN Charter)
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A law of treaties or lawS of treaties?
One set of rules applicable to all? Cf
case study of reservations to human
rights treaties (Pt 5 below)
Codification or Progressive
Development?
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“the more precise formulation and
systemisation of rules of international law in
fields where there already has been
extensive State practice, precedent and
doctrine”(ILC Statute)
“the preparation of draft Conventions on
subjects which have not yet been regulated
by international law or in regard to which the
law has not yet sufficiently developed in the
practice of States” (ILC Statute)
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VCLT contains elements of both
codification (of existing CIL) and of
progressive development (preamble,
7th indent)
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Article 9(2); Articles 19-23; Articles 4041; Articles 42-72 all contain elements
of progressive development and hence
only bind States Parties UNLESS
crystallise in CIL
Some Terminology…..
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Article 2(1)(g): State is bound by the
treaty only when it has both given its
consent to be bound AND the treaty has
entered into force - only then may it be
called a “Contracting Party”
“Contracting State” signifies consent but
term applicable whether or not treaty is
in force
Examples of pre-existing CIL
codified in the VCLT
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Fundamental change of circumstances
(Article 62) (Fisheries Jurisdiction Case
1973)
termination and breach (Namibia
Advisory Opinion 1971)
Articles 31-33 on treaty interpretation
(Beagle Channel Arbitration)
Interaction between treaty and
custom
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“In so far as this contention is based on the view that Article 6
of the Convention has had the influence, and produced the
effect, described, it clearly involves treating that Article as a
norm-creating provision which has generated a rule which, while
only conventional or contractual in origin, has since passed into
the general corpus of international law, and is now accepted as
such by the opinio juris, so as to have become binding even for
countries which have never, and do not, become parties to the
Convention. There is no doubt that this process is a perfectly
possible one and does from time to time occur: it constitutes
indeed one of the recognised methods by which new rules of
customary international law may be formed. At the same time,
this result is not lightly to be regarded as having been attained.”
(1969 NSCS Cases)
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Can’t bind 3d parties w/o their consent BUT
3d parties may be bound by the treaty rule if
also reflected as a rule of CIL; this possibility
expressly preserved in Article 38 VCLT
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e.g. Article 2(4) UN Charter also CIL: 1986
Nicaragua Case
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influence of treaty negotiation on CIL norm
crystallisation e.g. development of EEZ
concept during LOSC negotitations
3. WHAT IS A TREATY?
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Article 2(1)(a) VCLT definition
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1. BETWEEN STATES
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2. IN WRITTEN FORM
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3. GOVERNED BY INTERNATIONAL LAW
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4. SINGLE INSTRUMENT OR TWO OR MORE
RELATED INSTRUMENTS
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5. WHATEVER ITS PARTICULAR DESIGNATION
“Whatever its particular designation”
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Convention (1982 LOSC)
Treaty (e.g. of peace, extradition,etc.)
Agreement (e.g. cultural cooperation)
Exchange of Notes (Cameroon v
Nigeria, ICJ, 10 October 2002)
Protocols (to ICCPR; Kyoto Protocol to
1992 FCCC)
Charter (e.g. UN Charter; but not
CERDS)
What is in a name? EFFECT is
what counts….
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Aegean Sea Continenal Shelf Case
(1978) “no rule of international law which
might preclude a joint communique
constituting an international agreement to
submit a dispute to arbitration or judicial
settlement”
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Qatar/Bahrain (1994) (status of 1990
Minutes as binding agreement
notwithstanding alleged contrary intent)
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Article 3 VCLT: even if not in writing,
does not necessarily deprive
“agreement” of legal effect
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Nuclear Tests Cases (1974) (unilateral
declarations - oral not written undertakings
yet nonetheless unilateral acts binding upon
France) Role of intent here?
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Frontier Dispute Case (1986) (intent key
factor in depriving Presidential “quip” of legal
effect)
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“One should probably distinguish the
question whether oral statements, or
unilateral declarations, create a legal
obligation, from the question whether
they constitute treaties or agreements”
(Jennings and Watts)
such statements governed by IL though
not directly by the VCLT owing to the
requirement of writing
exs of Nuclear Tests Cases (1974) and
Eastern Greenland Case (1933)