Why States Comply With International Law
In the realm of global politics, a fundamental mystery persists: why do sovereign states, possessing supreme authority over their territories, choose to restrict their own behavior by adhering to international law? Unlike domestic legal systems, international law lacks a centralized legislature, a mandatory court system with universal jurisdiction, and a global police force to enforce “commandments.” Yet, the reality of international relations is that most states comply with most of their obligations most of the time.
This article explores the sophisticated legal theories and practical motivations—ranging from reputation and reciprocity to internal socialization—that ensure the stability of our global legal order.
The Foundation of Obligation: Pacta Sunt Servanda
At the heart of international law lies the foundational principle of Pacta Sunt Servanda (Agreements Must Be Kept). Codified in Article 26 of the Vienna Convention on the Law of Treaties (1969), this principle asserts that every treaty in force is binding upon the parties to it and must be performed by them in good faith.
Example
When two countries sign a boundary treaty, they are not just making a promise; they are creating a legal “lock” that ensures neither side can unilaterally change the border without violating the very fabric of international law.
Leading Case: Gabčíkovo–Nagymaros Project (Hungary v. Slovakia, 1997)
The International Court of Justice (ICJ) emphasized that Hungary could not simply back out of a 1977 treaty regarding a dam system on the Danube River. The Court ruled that even if circumstances change, the principle of Pacta Sunt Servanda requires states to seek a negotiated solution rather than simply ignoring their legal obligations.
The Realist Perspective: Power, Interest, and Reciprocity
Realism suggests that states comply when it serves their national interest. A key mechanism here is Reciprocity. If State A violates the diplomatic immunity of State B’s ambassadors, State B will likely retaliate in kind.
- Reciprocal Compliance: “I will follow the rules as long as you do, because the benefit of the rule is greater than the benefit of breaking it.”
Leading Case: United States Diplomatic and Consular Staff in Tehran (USA v. Iran, 1980)
When Iranian students seized the US Embassy, the ICJ ruled that Iran violated the Vienna Convention on Diplomatic Relations. While enforcement was difficult, the case highlighted that the “sanctity of the envoy” is a reciprocal interest; if states do not protect foreign diplomats, their own diplomats abroad become targets.
The Liberal and Institutionalist View: Transaction Costs
Institutionalists argue that international law provides a “roadmap” for cooperation. Compliance reduces transaction costs—the time and effort it takes to negotiate every single interaction from scratch.
- Standardization: International law sets standards (such as civil aviation rules or postal unions) that make the world run smoothly.
Example
The International Civil Aviation Organization (ICAO) sets rules for air traffic control. States comply not because they fear a global police force, but because they want their planes to land safely in other countries.
Constructivism and the Power of Legitimacy
Constructivists believe that states comply because they want to be seen as “good international citizens.” Laws carry a certain legitimacy (the “right process”). If a rule is created through a fair and transparent process, states feel a moral and social pull to obey it.
Leading Case: Whaling in the Antarctic (Australia v. Japan: New Zealand Intervening, 2014)
Despite the cultural importance of whaling to Japan, when the ICJ ruled that Japan’s “scientific” whaling program violated the International Convention for the Regulation of Whaling, Japan initially halted its program in the Antarctic. This demonstrated the “compliance pull” of a high-status international court.
The Role of Domestic Legal Systems and Internalization
Frequently, international law is “brought home.” Once a treaty is incorporated into a country’s domestic laws, it is enforced by local judges and police.
- Direct Effect: In some countries, international treaties are automatically part of the law of the land (Monism).
Example
If a state signs a human rights treaty and integrates it into its constitution, a citizen can sue their own government in a local court for a violation of international law.
Leading Case: A v Secretary of State for the Home Department (2004)
In the UK, the House of Lords (now the Supreme Court) used the European Convention on Human Rights (an international treaty) to rule that the indefinite detention of foreign terror suspects without trial was unlawful. Here, the state complied with international law because its own domestic courts demanded it.
The Shadow of the Future: Reputation and Credibility
In a globalized economy, a state’s reputation is its most valuable currency. States that frequently break international law are seen as “pariahs.”
- Cost of Non-Compliance: A state that violates investment treaties will see foreign investors flee.
- A state that violates trade agreements (WTO rules) will face legal sanctions and a loss of market access.
Example
The World Trade Organization (WTO) Dispute Settlement Body allows injured states to “suspend concessions” (apply tariffs) against a member that breaks trade rules.
Summary Table: Why States Comply With International Law
| Perspective | Core Reason for Compliance | Illustrative Example |
|---|---|---|
| Legal | Binding force of treaties | Pacta Sunt Servanda |
| Realist | Reciprocity and retaliation | Diplomatic immunity |
| Institutionalist | Reduced transaction costs | ICAO aviation rules |
| Constructivist | Legitimacy and moral pull | ICJ whaling judgment |
| Domestic Law | Internal enforcement | UK human rights cases |
| Reputation | Future credibility | WTO sanctions |
Conclusion: A Web of Interdependence
Why do states comply? It is rarely for one single reason. Instead, it is a combination of:
- Legal Duty: The foundational weight of Pacta Sunt Servanda.
- Self-Interest: The realization that a lawless world is more expensive and dangerous.
- Reputation: The desire to remain a credible partner in trade and security.
- Domestic Pressure: The enforcement of international norms by local courts and civil society.
While international law is not perfect, it functions because states recognize that the “rules of the road” are what prevent global anarchy. Compliance is not just a moral choice; it is a calculated, structural necessity for the modern state.
Written By: Judge Nazmul Hasan
Senior Judicial Magistrate | Prime Minister Gold Medalist
Profile Overview
p>Nazmul Hasan is a highly accomplished judicial officer and legal scholar from Bangladesh, distinguished by a rare blend of judicial service excellence and unparalleled academic achievement.
Professional Expertise
| Title | Achievement / Service | Details |
|---|---|---|
| Senior Judicial Magistrate | Bangladesh Judicial Service (BJS) | Serving as a Senior Judicial Magistrate, demonstrating profound expertise in dispensing justice and administering court procedures. |
| Service Rank | 11th Bangladesh Judicial Service (BJS) | Secured the 7th Merit Position overall in the rigorous 11th BJS competitive examination, marking an exceptional start to a distinguished judicial career. |
Academic Distinction
| Qualification | Institution | Recognition |
|---|---|---|
| LL.B. (Hons.) | University of Rajshahi | First Class First (Top of the Cohort), signifying ultimate academic mastery in undergraduate legal studies. |
| LL.M. | University of Rajshahi | Achieved First Class standing, further solidifying expertise and specialized knowledge in advanced legal disciplines. |
Honors & Achievements (Awards of Excellence)
- Prime Minister Gold Medalist (2017)
Awarded the nation’s most prestigious academic honor for outstanding performance across all disciplines at the university level. - Agrani Bank Gold Medalist for Academic Excellence (2023)
Recognized with this distinguished medal for sustained academic excellence and leadership in the field of law.
Contact Information
Email: [email protected]
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