Customary International Law: Definition, Elements, and Evidence

Question 1

Which of the following is not an essential element of customary international law?

Accepted Answer

Treaties

Answer

State practice

Answer

Opinio juris

Answer

Consistency

Question 2

How does state practice contribute to the formation of customary international law?

Accepted Answer

It provides evidence of state behavior

Answer

It creates new rules of international law

Answer

It interprets existing rules of international law

Answer

It enforces rules of international law

Question 3

What is opinio juris and how does it contribute to customary international law?

Accepted Answer

The belief that a particular practice is legally binding

Answer

The intent to be bound by a particular rule

Answer

The actual behavior of states

Answer

The interpretation of treaties by international courts

Question 4

Which is an example of customary international law?

Accepted Answer

The principle of non-intervention

Answer

The Vienna Convention on Diplomatic Relations

Answer

The United Nations Charter

Answer

The Rome Statute of the International Criminal Court

Question 5

What is a fundamental requirement for the formation of customary international law?

Accepted Answer

Consistent state practice

Answer

State consent

Answer

Treaty ratification

Answer

Judicial decisions

Question 6

How has the relationship between customary international law and international conventions transformed?

Accepted Answer

Conventions and customary law are now interconnected and work together.

Answer

Conventions have gradually replaced customary law as the primary source of international law.

Answer

Customary law has lost its significance due to the increase in conventions.

Answer

Customary law remains largely unaffected by the development of conventions.

Question 7

Which of the following is the best definition of 'opinio juris'?

Accepted Answer

A consensus of state opinion that a particular practice is obligatory under international law

Answer

A belief by states that a particular practice is simply customary

Answer

A formal declaration by a state that it accepts a certain practice as binding

Answer

An interpretation of a treaty by an international court or tribunal

Question 8

Which of the following is a key characteristic of customary international law?

Accepted Answer

It is unwritten

Answer

It is created by the consent of all states

Answer

It is only binding on states that have explicitly accepted it

Answer

It is easily amended or repealed

Question 9

Which of the following is the most common way for states to demonstrate their acceptance of a customary international law rule?

Accepted Answer

Passing legislation

Answer

Making diplomatic statements

Answer

Participating in international conferences

Answer

Ratifying treaties

Question 10

Which of the following is NOT a role of international courts and tribunals in relation to customary international law?

Accepted Answer

Creating new customary international law rules

Answer

Determining the existence of customary international law rules

Answer

Interpreting customary international law rules

Answer

Enforcing customary international law rules

Question 11

What is the significance of opinio juris in the formation of CIL?

Accepted Answer

It establishes states' subjective belief in the legal obligation of a particular practice

Answer

It codifies existing customary norms into treaties

Answer

It provides binding judicial precedents for future cases

Answer

It determines the geographical boundaries of a customary rule

Question 12

Which source of international law is widely regarded as the primary repository of Customary International Law?

Accepted Answer

Customary state practice

Answer

International treaties

Answer

Resolutions adopted by the United Nations General Assembly

Answer

Decisions rendered by international tribunals

Question 13

The process by which CIL is gradually formed and developed is known as:

Accepted Answer

Accretion

Answer

Prescription

Answer

Codification

Answer

Adjudication

Question 14

The doctrine of persistent objector allows states to:

Accepted Answer

Exclude themselves from the application of a newly emerging customary rule

Answer

Codify existing customary rules into binding treaties

Answer

Create new customary rules based on their own preferences

Answer

Amend existing customary rules to suit their national interests

Question 15

The International Court of Justice (ICJ) plays a crucial role in:

Accepted Answer

Identifying, interpreting, and applying Customary International Law

Answer

Enforcing compliance with Customary International Law

Answer

Creating new Customary International Law through its judgments

Answer

Modifying existing Customary International Law based on its decisions

Question 16

Identify a primary criticism of customary international law.

Accepted Answer

Determining customary practices across states poses challenges.

Answer

Customary international law is overly rigid, hindering adaptation.

Answer

It exclusively binds states that have explicitly consented.

Question 17

Which of the following is NOT an element of customary international law?

Accepted Answer

Written agreement

Answer

Longstanding and consistent practice

Answer

State practice

Answer

Opinio juris

Question 18

What is the term for the subjective belief that a particular practice is legally binding?

Accepted Answer

Opinio juris

Answer

Erga omnes

Answer

Jus cogens

Answer

Pacta sunt servanda

Question 19

Which of the following is a characteristic of jus cogens?

Accepted Answer

It represents a fundamental and overriding principle of international law.

Answer

It can be created through state practice alone.

Answer

It is binding on all states, regardless of consent.

Question 20

What is the process by which a state objects to a customary international law norm and thereby excludes itself from being bound by it?

Accepted Answer

Persistent objector

Answer

Denunciation

Answer

Abrogation

Answer

Reservation

Question 21

Which of the following is an example of a multilateral treaty that has contributed to the development of customary international law?

Accepted Answer

United Nations Convention on the Law of the Sea

Answer

Treaty of Versailles

Answer

North American Free Trade Agreement

Question 22

What is the relationship between customary international law and general principles of law?

Accepted Answer

They are considered subsidiary sources of international law.

Answer

Customary international law takes precedence over general principles of law.

Answer

General principles of law are only applicable in the absence of customary international law.

Question 23

In which case did the International Court of Justice (ICJ) recognize the existence of a customary international law norm prohibiting genocide?

Accepted Answer

Bosnia and Herzegovina v. Serbia and Montenegro

Answer

Barcelona Traction

Answer

Nicaragua v. United States

Answer

Corfu Channel

Question 24

Which of the following is a key criticism of the doctrine of customary international law?

Accepted Answer

It can be difficult to determine whether a particular practice is sufficiently widespread and consistent to constitute a customary norm.

Answer

It is too rigid and inflexible to adapt to changing circumstances.