Pacta Sunt Servanda, and No Excuse in Domestic Law
Chapter Eight
Syllabus topic 1, "Environmental Federalism and International Order"
Pages 23 to 25 of 663
In one line
Two articles of the Vienna Convention decide half the arguments in this book: a treaty in force binds the parties and must be performed in good faith, and a State may not point to its own law as a reason for not performing.
In exam wording: Article 26 of the Vienna Convention on the Law of Treaties 1969 states the rule pacta sunt servanda, that every treaty in force is binding upon the parties to it and must be performed by them in good faith; Article 27 provides that a party may not invoke the provisions of its internal law as justification for its failure to perform a treaty.
Why the law has this at all
Because without it, treaties would be worth nothing. If a State could escape an obligation by passing a domestic statute inconsistent with it, every treaty would last exactly as long as the government that made it. The Latin tag pacta sunt servanda means "agreements must be kept", and it is the oldest rule in the subject.
Article 27 is the sharper of the two, and it is the one Indian students most often get wrong. It does not say that a treaty overrides Indian law inside India. It says that India cannot use Indian law as an excuse when another State complains internationally.
The provisions
Article 26. Every treaty in force is binding upon the parties to it and must be performed by them in good faith.
Article 27. A party may not invoke the provisions of its internal law as justification for its failure to perform a treaty. This rule is without prejudice to Article 46.
Article 46, which Article 27 preserves, is the narrow exception: a State may not claim that its consent was invalid because it violated its own law on competence to conclude treaties, unless the violation was manifest and concerned a rule of fundamental importance.
The two legal orders, and why this confuses people
Here is the point that has to be understood before the federalism chapters make sense.
Internationally, India is bound the moment it ratifies. If it does not perform, it is in breach, and Article 27 forbids it to plead the state of Indian law.
Domestically, ratification changes nothing. A treaty is not self-executing in India. Until Parliament legislates, no Indian court can enforce a treaty obligation against a private person, and no private person acquires a right under it.
So India can be simultaneously in breach internationally and perfectly correct domestically. That is not a contradiction; it is two legal orders with different rules of recognition, and Article 27 is the rule that stops the second from being an answer to the first.
Pacta Sunt Servanda, and No Excuse in Domestic Law
Worked example
Suppose India ratifies a convention requiring every Party to prohibit the export of a listed chemical from 2030. Parliament does not legislate. In 2031 an Indian company exports the chemical lawfully under Indian law.
- Is the company liable? No. Indian law permits the export and the treaty is not part of Indian law.
- Is India in breach? Yes. India undertook to prohibit the export and has not done so.
- Can India say "our Parliament has not legislated"? No. Article 27 forbids exactly that plea.
- What can India do? Legislate, using Article 253 of the Constitution, which empowers Parliament to make any law for the whole or any part of India for implementing a treaty.
That worked example is the reason MU put federalism at the head of the syllabus.
Good faith, and what it adds
Article 26 does not merely say a treaty binds. It says it must be performed in good faith. That adds three things a tribunal has actually relied on:
- A party may not use a discretion conferred by the treaty in a way that defeats its purpose. This is the reasoning behind the Court's approach in the Whaling in the Antarctic case, where Japan's own characterisation of its programme as scientific was held to be reviewable against an objective standard.
- A party must not frustrate performance by the other side. In Gabcikovo-Nagymaros Project, the Court held that Hungary could not rely on a state of necessity it had itself helped to bring about.
- Where the treaty requires cooperation, the cooperation must be genuine. That is the sense in which the Tribunal in the MOX Plant case called the duty to cooperate a fundamental principle in the prevention of pollution of the marine environment.
What it does NOT mean
Article 27 does not make treaties part of Indian law. It is a rule about excuses, not about incorporation.
It does not override the Constitution. Internationally India is bound; domestically the Constitution is supreme. If the two conflict the answer is legislation or amendment, not a claim that the treaty prevails.
Pacta sunt servanda is not absolute. Articles 60 to 62 provide for termination or suspension for material breach, supervening impossibility and fundamental change of circumstances. Hungary argued all three in Gabcikovo and lost on all three, which is the standing lesson about how narrow those doors are.
Quick revision
- Article 26: a treaty in force binds the parties and must be performed in good faith.
- Article 27: internal law is no excuse, subject only to Article 46's manifest violation of a fundamental rule on competence.
- Two orders: bound internationally on ratification, unenforceable domestically until legislation.
- Good faith adds: no abuse of discretion, no frustration of the other party, genuine cooperation.
- The exits from a treaty are Articles 60 to 62, and they are narrow.
Pacta Sunt Servanda, and No Excuse in Domestic Law
Test yourself
1. India ratifies a convention and does not legislate. A citizen sues to enforce it. What happens? The suit fails, because the treaty is not part of Indian law. India's international breach is a separate matter and Article 27 prevents India from pleading the absence of legislation as a defence internationally.
2. What does "in good faith" add to Article 26? It forbids abuse of a discretion the treaty confers, frustration of the other party's performance, and sham cooperation.
3. What is the one exception Article 27 preserves? Article 46: consent may be invalidated by a violation of internal law on competence to conclude treaties, but only if the violation was manifest and concerned a rule of fundamental importance.
The rest of this subject
These notes are cut from the University's printed syllabus. Open the syllabus itself, or the past papers, for the same subject.