Exploring the Foundations of International Human Rights Law

When we talk about protecting human rights globally, we often hear about treaties, courts, and declarations – but where does international human rights law actually come from? What makes a particular rule legally binding on a government, and what merely shapes expectations without enforceable consequences? Understanding the sources of international human rights law is essential for anyone engaging with human rights advocacy, criminal justice, or public interest litigation. According to the Office of the UN High Commissioner for Human Rights (OHCHR), the backbone of this framework consists of international treaties and customary law, supplemented by declarations, judicial decisions, and other instruments that shape its development and application.

The foundational map: Article 38 of the ICJ Statute 🔗

Before diving into each source, it helps to know where the formal list comes from. Article 38(1) of the Statute of the International Court of Justice (ICJ) is widely regarded as the most authoritative enumeration of the sources of international law. It directs the Court to apply: international conventions (treaties), international custom, general principles of law, and – as subsidiary means – judicial decisions and the writings of highly qualified legal scholars. This framework, originally drafted in 1920 for the Permanent Court of International Justice, continues to guide how international law is understood and applied across courts and legal systems worldwide.

Conventions and treaties: the primary binding source 🔗

International conventions – also called treaties, covenants, or protocols – are formal, written agreements between states that create legally binding obligations. Under Article 38(1)(a) of the ICJ Statute, treaties are the most prominent source of international law and are the only mechanism through which two or more states can formally enter into direct legal relations. When a state ratifies a treaty, it agrees to be legally bound by its terms and must align its domestic law accordingly.

In the human rights context, the most significant treaties are clustered within the International Bill of Human Rights – which comprises the Universal Declaration of Human Rights (UDHR), the International Covenant on Civil and Political Rights (ICCPR, 1966), and the International Covenant on Economic, Social and Cultural Rights (ICESCR, 1966). The two Covenants entered into force in 1976, converting the aspirational language of the UDHR into binding state obligations. Today, all 193 UN member states have ratified at least one of the nine core international human rights treaties, and 80% have ratified four or more.

Core human rights treaties 🔗

Beyond the two Covenants, several specialized treaties have expanded human rights protections to address specific concerns – the Convention on the Elimination of All Forms of Racial Discrimination (CERD), the Convention Against Torture (CAT), the Convention on the Rights of the Child (CRC), and the Convention on the Elimination of All Forms of Discrimination against Women (CEDAW), among others. India has ratified several of these, including the ICCPR, ICESCR, CERD, CRC, and CEDAW, making them legally applicable under India’s international obligations.

Regional treaties also play a significant role. The European Convention on Human Rights, the American Convention on Human Rights, and the African Charter on Human and Peoples’ Rights each create legally binding obligations within their respective regions, often accompanied by regional courts with enforcement powers. While India is not party to any regional human rights treaty (no such mechanism exists in Asia), understanding these frameworks is critical for comparative human rights advocacy.

Customary international law: unwritten but binding 🔗

Not all binding international law emerges from written agreements. Customary international law (CIL) consists of rules that arise from the consistent and general practice of states, carried out with a sense of legal obligation. Article 38(1)(b) of the ICJ Statute defines it as “international custom, as evidence of a general practice accepted as law.” This definition captures two essential elements: state practice (what states actually do) and opinio juris (the belief that the practice is legally required, not merely courtesy).

What counts as state practice? Legal scholars like Ian Brownlie identify it broadly – including diplomatic correspondence, official statements, government manuals, legislative acts, and judicial decisions at the national level. When enough states follow a rule consistently, and do so because they believe it is legally obligatory, that rule crystallizes into customary international law, binding even on states that have not signed any relevant treaty.

Why CIL matters in practice 🔗

Customary international law fills critical gaps in treaty law. Customary IHL (international humanitarian law) complements treaty law and applies even in situations where no specific treaty governs. Importantly, some norms – called jus cogens or peremptory norms – hold such fundamental status that no derogation is ever permitted. The prohibitions on genocide, slavery, torture, and crimes against humanity are universally recognized as jus cogens, binding all states regardless of treaty ratification. These norms exist above ordinary customary law and can even override conflicting treaty provisions.

Judicial decisions: influential but not universally binding 🔗

Courts – both international and regional – play a vital role in shaping what international human rights law means in practice. However, their legal status as a “source” of law requires careful understanding. Under Article 38(1)(d) of the ICJ Statute, judicial decisions are classified as only a subsidiary means for determining rules of law – not a primary source in themselves. The ICJ’s own decisions bind only the parties to the specific case before it, and there is no formal doctrine of precedent (stare decisis) in international law.

That said, the practical influence of judicial decisions is considerable. The ICJ regularly refers to its own prior rulings for consistency. The European Court of Human Rights (ECtHR) issues binding judgments against member states of the Council of Europe, directly shaping domestic legal systems. The Inter-American Court of Human Rights similarly issues binding decisions within its jurisdiction. Meanwhile, quasi-judicial bodies – such as the UN Human Rights Committee under the ICCPR – issue views and general comments that, while not formally binding, carry significant persuasive authority. International criminal tribunals like the ICC have jurisdiction over genocide, war crimes, and crimes against humanity, further reinforcing accountability norms through judicial practice.

The distinction between binding and persuasive authority 🔗

For a law student or advocate, it is important to distinguish between decisions that are legally binding on a state and those that are persuasive. A judgment of the ECtHR binds the responding state; an advisory opinion of the ICJ does not formally bind anyone but carries enormous moral and legal weight. Indian courts have frequently looked to international human rights jurisprudence – particularly ECtHR and UN committee decisions – as persuasive authority when interpreting fundamental rights under the Constitution of India.

Declarations and resolutions: soft law with hard impact 🔗

Declarations and resolutions passed by international bodies like the UN General Assembly are generally not legally binding. They are often described as “soft law” – non-binding instruments that nevertheless shape the development of human rights norms, influence state behavior, and sometimes crystallize into customary international law over time.

The most prominent example is the Universal Declaration of Human Rights (UDHR), adopted on December 10, 1948, by the UN General Assembly. It was deliberately framed as a declaration – not a treaty – because Eleanor Roosevelt and other framers believed this would allow for broader adoption without the complications of ratification. The UDHR itself does not carry the force of binding law. However, many legal scholars cite the UDHR as evidence of customary international law, and it has inspired over 80 international human rights treaties and declarations, along with numerous national constitutions and domestic laws. Notably, India played a significant role in shaping the UDHR – Indian delegate Hansa Mehta was instrumental in changing the first article’s language from “all men are born free” to “all human beings are born free,” an important step toward gender-inclusive human rights language.

The UDHR’s role in Indian law 🔗

In India, the UDHR’s influence is well-documented in judicial history. The Supreme Court of India in Keshavananda Bharati v. State of Kerala observed that “the Universal Declaration of Human Rights may not be a legally binding instrument but it shows how India understood the nature of human rights at the time the Constitution was adopted.” India’s Fundamental Rights under Part III of the Constitution, and the Directive Principles under Part IV, closely mirror the civil, political, economic, and social rights outlined in the UDHR – reflecting the fact that both documents drew on common sources of rights philosophy. The Supreme Court has consistently used UDHR provisions as an interpretive aid when expanding the scope of constitutional rights.

Declarations versus treaties: understanding the difference 🔗

The distinction matters for advocacy. A declaration sets out aspirational standards – a vision of what the international community believes human rights should be. A treaty creates a legal obligation and is monitored by treaty bodies that hold states accountable. As the UN’s Assistant Secretary-General for Human Rights has noted, the UDHR has become a yardstick for measuring state commitments – particularly through mechanisms like the Universal Periodic Review – even without being a binding treaty. Over time, many rights first expressed in the UDHR have been codified into binding conventions, effectively giving them the force of law through a different legal vehicle.

How these sources interact 🔗

These four sources do not operate in isolation. A human rights norm often begins as a declaration, becomes a treaty obligation through codification, is reinforced by consistent state practice that develops into customary international law, and is then clarified and applied through judicial decisions. According to OHCHR, while treaties and customary law form the structural backbone of international human rights law, declarations, guidelines, and principles contribute to its interpretation and development. For advocates and lawyers working in human rights – especially in criminal justice contexts – understanding which source a particular norm comes from determines how it can be invoked, whether before a domestic court, a treaty monitoring body, or an international tribunal.

What do you think? Given that the UDHR is not legally binding, should states that consistently violate its principles face stronger international consequences – or does the absence of binding force make soft law instruments like the UDHR ultimately toothless? And as India continues to engage with international human rights mechanisms, how should domestic courts balance treaty obligations with constitutional provisions when the two appear to conflict?

References

1. https://www.ohchr.org/en/instruments-and-mechanisms/international-human-rights-law
2. https://guides.loc.gov/public-international-law/sources-of-law
3. https://newjurist.com/article-38-of-the-statute-of-the-international-court-of-justice-a-complete-reference-point-for-the-sources-of-international-law/
4. https://www.un.org/en/about-us/udhr/foundation-of-international-human-rights-law
5. https://libraryguides.law.uic.edu/c.php?g=1297011&p=9527334
6. https://en.wikipedia.org/wiki/Sources_of_international_law
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8. https://guides.lib.uw.edu/c.php?g=449883&p=3071124
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10. https://en.wikipedia.org/wiki/International_human_rights_law
11. https://en.wikipedia.org/wiki/Universal_Declaration_of_Human_Rights
12. https://nhrf.no/blog/indias-contribution-to-the-udhr-a-remarkable-achievement
13. https://blog.ipleaders.in/universal-declaration-of-human-rights-udhr/
14. https://unfoundation.org/blog/post/70-years-of-impact-insights-on-the-universal-declaration-of-human-rights/