Problem 2: From law in treaties to law about treaties PART I
E-lessons: 9 and 22
Literature: Chapter 3
Legislation: Vienna Convention on Law of Treaties
Case Law: Reservations to the convention on the prevention and punishment of the crime of genocide,
Hungary v. Slovakia, Democratic Republic of the Congo v. Rwanda
What is the Law of Treaties?
Vienna Convention on the Law of Treaties
One of the regimes of public international law is the law of treaties. This regime is largely part of
customary international law (internationaal gewoonterecht), but has also been codified in large part, in
the Vienna Convention on the Law of Treaties 1969 and the Vienna Convention on the Law of Treaties
between States and International Organizations or between International Organizations 1986.
General introduction
One of the oldest regimes of public international law is the law of treaties. Treaties have been
concluded between states as primary subjects of international law for centuries.
Over time, a vast body a rules has crystallized, with regards to all aspects surrounding creation,
application and termination of treaties. In fact, treaties form a crucial basis of relations between states
and also form the legal basis of international organizations.
Moreover, many international legal disputes arise out of the interpretation, application or termination of
treaties. An example is the Gabcikovo-Nagymaros case, which involved a bilateral treaty between
Hungary and Czechoslovakia.
The law of treaties is governed by two separate mechanisms:
1. The 1969 Vienna Convention on the Law of Treaties (VCLT);
2. Customary international law.
Since the VCLT is mostly a codification of customary international law, these sources of law
overlap to a large degree.
One of the difficulties that one encounters when comparing the VCLT to customary international law is
determining which provisions of the VCLT reflect customary international law, since the VCLT is not
explicit in this regard.
A related difficulty concerns the question of how customary provisions on the law of treaties operate.
There seems to be a general consensus exists that provisions governing treaty interpretation, material
breach and fundamental change of circumstances are all part of customary international law.
The VCLT is considered to be a progressive (vooruitstrevend) document. In other words, when it was
adopted in 1969, some of its provisions were understood to be presumptive evidence of emerging
rules (verrmoedelijk bewijs van nieuwe regels).
The scope of the VCLT is limited, however.
» First, the VCLT is solely applicable to treaties between states (Article 1 VCLT). It does not
contain provisions that are applicable to treaties concluded between states and international
organizations, or to treaties concluded between international organizations;
» Second, the VCLT does not contain any provisions on state succession to treaties (that is
when a successor state forms and replaces a predecessor state);
» Third, treaties may be affected by various factors, such as situations of armed conflict, but the
VCLT is silent on such effects.
The legal philosopher, H.L.A. Hart, has made a theoretical distinction between two types of rules in
public international law: primary and secondary.
» Primary rules concern substantive obligations such as the prohibition of the use of force;
» Secondary rules govern the interpretation and application of the primary rules. They are rules
about rules;
» Examples of secondary rules include the regimes of state responsibility and the law of
treaties.
Relationship between treaty law and substantive law
In principle, treaty law is a distinct body of secondary rules of public international law. primary and
secondary rules are two separate categories of law and, thus, cannot be in conflict with each other.
, » It would be illusory to assume they do not influence each other;
» The secondary rules govern the application, interpretation and enforcement (handhaving) of
primary rules;
» Especially with regard to the enforcement, it is relevant to understand the effect of
secondary rules on primary rules.
Democratic Republic of the Congo v. Rwanda
This case demonstrates the interplay between primary and secondary rules.
The Democratic Republic of the Congo ("DRC”) filed an application at the ICJ, alleging grave human
rights breaches committed by Rwanda.
In order to lawfully file an application at the International Court of Justice, a basis for jurisdiction must
first be found in some treaty or other legal instrument.
In this case, the DRC relied on multiple human rights treaties, which refer to the International Court of
Justice as the mandatory body for judicial dispute settlement. The ICJ discussed the matter
concerning its jurisdiction in paragraphs 15, 29, 56, 57 and 70.
The Court concludes in paragraph 70 that, having regard to Rwanda's reservation to Article IX of the
Genocide Convention, this Article cannot constitute the basis for the jurisdiction of the Court in the
present case.”
Two basic principles
The law of treaties is based on two foundational principles (grondbeginselen):
1. The first is the corollary, consequence, of state sovereignty: treaties need to be based on the
free consent of states;
2. The second foundational principle specifies that the freedom of states is not unlimited: once
consent to be bound has been expressed and the treaty has entered into force, the treaty shall
be kept by the parties in good faith. This is the principle of good faith/ pacta sunt servanda,
which is codified in Article 26 VCLT.
Once in force, treaties are supposed to be performed. This too is said to follow from sovereignty, but
stresses the responsible side of sovereignty, premised (vooropgesteld) as it is on the thought that
states know what they are getting themselves into when concluding treaties.
» Even contrary domestic law, is not a valid excuse for failing to perform treaty obligations, at
least not under international law (Article 27 VCLT).
The principle of good faith/ pacta sunt servanda
One of the most fundamental principles of the law of treaties is that obligations under a treaty should
be performed in good faith, also known as the principle of pacta sunt servanda.
The underlying reason for this principle is that states possesses full sovereignty and are in no way
obliged to enter into treaty obligations with each other. The fact that states enter into treaty relations
out of their free will indicates that they will perform their treaty obligations in good faith.
Otherwise, entering into such obligations would be irrational (redeloos).
The principle of good faith has been codified in Article 26 VCLT and consists of two main elements:
1. The treaty in force is binding upon the parties;
2. The treaty must be performed by the parties in good faith.
The International Court of Justice has confirmed the importance of the principle of pacta sunt servanda
in the Gabcikovo-Nagymaros case in paragraphs 114 and 142.
What is a Treaty? How does it come into being?
Type of treaties (bilateral/ multilateral)
International law makes a general distinction between two types of treaties: bilateral and multilateral.
- Bilateral treaties concern an international agreement between two contracting parties;
- Multilateral treaties are agreements involving more than two state parties.
A treaty is defined in Article 2(1)(a) VCLT. This definition has several implications for the scope of
applicability of the VCLT.
First, the VCLT only applies to treaties between states.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller aee. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.65. You're not tied to anything after your purchase.