Citizenship · Year 10 · Human Rights and International Law · Summer Term

International Law: Treaties & Custom

Students are introduced to the sources and principles of international law, including treaties and customary law.

• National Curriculum Attainment Targets
• GCSE: Citizenship - International Law and Treaties

About This Topic

International law sets out rules for relations between states, and this topic focuses on its key sources: treaties and customary law. Treaties are formal, written agreements, such as the Universal Declaration of Human Rights or the Paris Climate Agreement, which states negotiate, sign, and ratify. Customary law develops from repeated state practices, like diplomatic immunity, that gain legal force through widespread acceptance. Students learn how these sources interact, with treaties often codifying customs, and explore enforcement via institutions like the International Court of Justice or UN Security Council.

In the GCSE Citizenship curriculum, this unit on Human Rights and International Law builds skills in analysis and evaluation. Students tackle key questions: distinguishing treaties from customs, tracing law creation and enforcement, and assessing state sovereignty barriers, where nations prioritize independence over obligations. Real-world examples, from Brexit treaty issues to South China Sea disputes, show law's practical limits and importance.

Active learning suits this topic well. Simulations of treaty talks or debates on sovereignty help students navigate abstract ideas through role-play and collaboration. These methods make enforcement challenges vivid, foster empathy for global perspectives, and link concepts to news, boosting retention and critical citizenship skills.

Key Questions

1. Explain the difference between international treaties and customary international law.
2. Analyze how international law is created and enforced.
3. Assess the challenges of state sovereignty in the application of international law.

Learning Objectives

• Compare the legal standing of a ratified treaty with a long-standing customary international practice.
• Analyze the mechanisms by which international law is created through state consent and general practice.
• Evaluate the effectiveness of international legal enforcement in situations where state sovereignty is asserted.
• Explain the role of international organizations, such as the International Court of Justice, in adjudicating disputes under international law.

Before You Start

The Role of the State

Why: Students need to understand the concept of a sovereign state as the primary actor in international relations before examining how states interact through international law.

Introduction to Global Governance

Why: Familiarity with international organizations and their basic functions provides context for understanding how international law is applied and enforced.

Key Vocabulary

Treaty	A formal, legally binding written agreement between two or more sovereign states, or between states and international organizations. Treaties are a primary source of international law, outlining rights and obligations.
Customary International Law	Law that arises from the consistent and general practice of states, accepted as law. It is unwritten and based on the principle that states follow certain practices out of a sense of legal obligation.
State Sovereignty	The supreme authority of a state within its territory, free from external control. It is a fundamental principle in international law, often creating tension with international legal obligations.
Jus Cogens	Peremptory norms of general international law from which no derogation is permitted. These are fundamental principles that bind all states, such as the prohibition of genocide or torture.
Ratification	The formal act by which a state confirms its consent to be bound by a treaty. This process typically involves domestic legislative approval before the treaty enters into force for that state.

Watch Out for These Misconceptions

Common Misconception

All international law comes from treaties.

What to Teach Instead

Customary law forms from state practices over time, without written documents, and binds even non-signatories. Role-plays of historical practices help students see this evolution, while group timelines clarify how customs influence treaties.

Common Misconception

International law works like domestic law with police enforcement.

What to Teach Instead

Enforcement relies on state consent, diplomacy, or sanctions, not centralized police, due to sovereignty. Debates on real cases reveal this gap, and simulations show why compliance varies, building nuanced understanding through peer discussion.

Common Misconception

Treaties automatically bind all countries.

What to Teach Instead

Only ratifying states are bound, though customs apply universally. Analyzing ratification processes in groups corrects this, as students track non-signatories' behaviors and debate implications for global issues like human rights.

Active Learning Ideas

Debate Pairs: Treaty vs Customary Law

Pair students to prepare arguments: one side defends treaties as clearer and more reliable, the other praises customary law's flexibility. Each pair presents for 3 minutes, then switches sides. Class votes on strongest points and discusses real examples like the Geneva Conventions.

40 min·Pairs

Simulation Game: Mock UN Treaty Negotiation

Assign roles as state representatives with conflicting interests, such as environmental vs economic priorities. Groups draft a short treaty over 20 minutes, then present for ratification vote. Debrief on ratification challenges and sovereignty issues.

50 min·Small Groups

Case Study Carousel: Enforcement Examples

Set up stations with cases like the ICJ Nicaragua ruling or UN sanctions on North Korea. Small groups rotate, noting creation, enforcement attempts, and sovereignty hurdles. Each group shares one insight in a whole-class summary.

45 min·Small Groups

Timeline Individual: Evolution of a Custom

Students research one custom, such as maritime boundaries, and create a timeline of practices leading to legal status. Include key treaties that codified it. Share digitally or on posters for class gallery walk.

30 min·Individual

Real-World Connections

• The United Nations Security Council's debates and resolutions on international conflicts, such as the ongoing situation in Ukraine, demonstrate the challenges of enforcing international law when powerful states assert their sovereignty.
• International climate negotiations, like the annual COP meetings, involve states drafting and signing treaties such as the Paris Agreement, showcasing the process of treaty creation and the subsequent need for domestic ratification and implementation.

Assessment Ideas

Discussion Prompt

Pose the following question to small groups: 'Imagine a new global crisis emerges requiring immediate international cooperation. Would it be more effective to create a new treaty or rely on existing customary international law? Justify your answer with specific examples of challenges and benefits for each.' Allow groups 10 minutes to discuss before sharing key points.

Exit Ticket

On a slip of paper, ask students to: 1. Define 'treaty' in their own words. 2. Provide one example of customary international law. 3. State one reason why enforcing international law can be difficult for states.

Quick Check

Present students with two scenarios: Scenario A describes a formal agreement signed by 50 countries, while Scenario B describes a practice followed by most countries for centuries, such as diplomatic immunity. Ask students to identify which is an example of a treaty and which is customary international law, and to briefly explain their reasoning for each.

Frequently Asked Questions

What is the difference between international treaties and customary law?

Treaties are explicit, written pacts states voluntarily enter, like the UN Charter, requiring signature and ratification. Customary law emerges from consistent practices states follow out of legal obligation, such as not invading embassies. Treaties offer clarity but bind fewer parties; customs ensure broad application. Students benefit from comparing examples side-by-side in debates.

How is international law created and enforced?

Creation happens via treaty negotiations or customary practice accumulation. Enforcement uses courts like the ICJ for disputes, UN resolutions, or sanctions, but lacks direct force due to sovereignty. Cases like Yugoslavia tribunals show mixed success. Active analysis of timelines helps students grasp these dynamics.

What challenges does state sovereignty pose to international law?

Sovereignty lets states reject external authority, leading to non-compliance, as in Russia's Ukraine actions despite treaties. Powerful nations evade sanctions easily. Yet, interdependence pushes cooperation on trade or climate. Role-plays expose these tensions, helping students evaluate law's real-world limits.

How can active learning help teach international law treaties and customs?

Active methods like mock negotiations or enforcement debates turn abstract rules into relatable scenarios. Students role-play state interests, draft treaties, or defend customs, experiencing sovereignty clashes firsthand. This builds critical analysis, empathy, and links to current events, far beyond passive reading. Group rotations ensure all voices contribute, deepening GCSE skills.