Customary Law

Meaning of Customary Law in the UK Legal System

The UK legal system incorporates a variety of legal traditions and structures, including common law, statute law, equity, and parliamentary law. among these, Customary Law represents a body of legal practices and norms that have been created through long-standing societal customs which were considered legally binding.

However, in modern times, the significance of Customary Law has gradually diminished due to the rise of statutory law and codification of many legal domains. Yet, it continues to play a role in shaping the legal landscape and influencing the development of more formal legislation.

Key Features of Customary Law

Understanding the key features of Customary Law is vital in order to distinguish it from other sources of law in the UK. Some of its most distinguishing characteristics include:

• Unwritten nature: Customary Law is not codified or documented in any official legal texts, making it largely unwritten and reliant on historical practices and traditions.
• Immemorial usage: For a custom to become Customary Law, it must have been practiced for an indefinite period of time, without any recorded instance of interruption or dispute.
• Consensus and acceptance: Customary Law requires the general population to have embraced a custom as a legal norm and for it to have been acknowledged, implicitly or explicitly, by the relevant authorities.
• Reasonableness: To be considered lawful, a custom must be reasonable and not violate any fundamental rights or principles of justice.
• Local or regional application: Customary Law is often specific to a particular geographic location or community and may not be universally applicable.
• Flexibility: As Customary Law evolves with society, it boasts the ability to adapt to changing social norms and circumstances over time.

Customary Law Examples in the UK

There are several examples of customary laws that have played an influential role in the UK legal system throughout history. Some of these include the following:

Modern Customary Law may not be as prevalent as it once was, but it still remains an important aspect of the UK legal system and heritage. It can be instructive in understanding the historical roots of the legal system and the many diverse cultural influences that have shaped it over time.

Customary Law vs Common Law

Customary Law and Common Law are both integral elements of the UK legal system; however, they are distinct from one another in their historical development, principles, and application. This section delves into the distinctions between Customary Law and Common Law, as well as the ways in which Customary Law has influenced the development of Common Law, to provide a comprehensive understanding of their respective roles and features.

Distinctions between Customary Law and Common Law

Customary Law and Common Law share certain similarities, as they both evolve from precedents and the unwritten traditions of the societies they serve. However, there are several important distinctions between the two that set them apart. The main differences between Customary Law and Common Law can be summarised as follows:

• Historical development: Customary Law is based on immemorial customs, traditions and societal norms that pre-date the formation of the legal system in England, whereas Common Law emerged after the Norman conquest in 1066. The latter was developed by judges through their interpretation of previous decisions and written statutes, which gradually created a unified body of law universally applicable across England and Wales.
• Sources and codification: Customary Law is unwritten and derived from long-standing societal customs, whereas Common Law is primarily based on judicial decisions and has been extensively documented in case law and legal texts, such as Blackstone's Commentaries on the Laws of England and various law reports.
• Reasoning and interpretation: In Customary Law, legal norms are based on the reasonableness and acceptance by the relevant local community, while in Common Law, judges rely on the doctrine of precedent and apply rules that have been established through judicial decisions in similar cases. This may lead to differing interpretations of legal principles, even when confronting identical factual situations.
• Geographical scope: Customary Law is often specific to a particular geographic location or community and may not be universally applicable, whereas Common Law provides a uniform legal framework across England and Wales, with certain principles recognised internationally.
• Subject matter: Customary Law often deals with traditional local matters, such as land usage, water rights, and local governance, while Common Law encompasses a wide range of fields, including contract, tort, property, and criminal law.
• Flexibility and adaptability: Both Customary Law and Common Law are flexible and adaptable to societal changes but in different ways. Customary Law is generally more flexible due to its close relationship with local communities, while Common Law evolves through a slow process of judicial decision-making and incremental changes reflecting the needs of broader society.

How Customary Law Influences Common Law

Although Customary Law and Common Law are distinct in their foundations and principles, Customary Law has had a significant impact on the development of Common Law over time. Customary Law influences Common Law in several ways, including:

• Developing legal principles: Customary Law is one of the historical roots of Common Law, providing a basis for various legal principles and doctrines that have subsequently been adopted and refined by Common Law judges in the interpretation of statutes and case law.
• Incorporating local knowledge: Customary Law has informed Common Law by introducing local customs, practices, and knowledge into the legal system, leading to the recognition of specific legal rights and obligations that might otherwise be overlooked in a more centrally governed legal system.
• Responsiveness to societal needs: Customary Law creates a channel for incorporating the needs and values of local communities into Common Law, leading to the adaptation of legal principles and the development of new legal rules that better align with the expectations, values, and circumstances of the society they serve.
• Role as a default law: In some situations where statute law or judicially developed Common Law does not provide a clear answer to a legal issue, Customary Law might fill the gap and operate as a default law, particularly in areas where local customs and traditions are particularly strong or significant.

Overall, while Customary Law and Common Law are distinct legal elements within the UK's legal system, they have a symbiotic relationship. Customary Law has played a significant role in shaping the development of Common Law over time, providing it with a foundation rooted in the values, traditions, and customs of the society it serves. In turn, Common Law has incorporated, refined, and built upon these customary principles to create a more cohesive and universally applicable legal system that has adapted to the ever-changing needs of society.

Customary International Law

Customary International Law is a significant component of international law, governing the relations between states and other international actors. It is formed from the consistent and general practices of states, conducted out of a sense of legal obligation. This section explores the role of Customary Law within the international legal system, its relationship to human rights law, and the factors that determine its formation.

Role of Customary Law in International Legal System

Customary International Law is a critical source of international law, along with treaties and general principles of law recognised by civilised nations. Its importance and role in the international legal system can be understood through the following aspects:

• Complementary source of law: Customary International Law operates alongside treaty law, filling gaps where no relevant treaty exists or where a treaty does not address a specific issue or aspect of an issue. It acts as a default rule, applying to states even in the absence of an explicit agreement.
• Adherence to the international legal system: All states are bound by Customary International Law, regardless of whether they have signed or ratified a particular treaty. This contributes to the stability and coherence of the international legal system, as it establishes a fundamental set of rules that apply universally, ensuring that states cannot avoid their legal obligations merely by not participating in a treaty.
• Reflection of global values and norms: Customary International Law is derived from the general practices of states and reflects the values, traditions, and norms of the international community. It evolves with the changing behaviour of states and their beliefs about what is required under international law, ensuring that the international legal system remains responsive to the needs and expectations of its constituent actors.
• Human rights protection: Customary International Law plays a vital role in the protection of human rights, as it often incorporates fundamental human rights principles that have become widely accepted by the majority of states.
• Resolution of disputes: Customary International Law provides a basis for the resolution of disputes between states, acting as a common framework for understanding the rights and obligations of parties in conflicts, as well as shaping the procedures and remedies available in international dispute settlement mechanisms.

Customary Human Rights Law in the UK and Abroad

Customary International Law plays an influential role in the recognition and protection of human rights at both the global and national levels. Customary human rights law in the UK and abroad can be identified through the following elements:

• Norms of customary human rights law: Customary human rights law encompasses a set of basic rights and principles recognised by the majority of states as binding legal obligations, such as the prohibition of torture, the right to a fair trial, and the principle of non-refoulement, which prohibits the forced return of refugees to a country where they face persecution.
• Incorporation into domestic law: Many customary human rights norms are incorporated into the domestic laws of states, including the UK, through legislation, judicial decisions, and constitutional provisions. For example, in the UK, the prohibition against torture is incorporated into domestic law through the Human Rights Act 1998, which gives effect to the rights contained in the European Convention on Human Rights.
• International monitoring and enforcement: Customary human rights law is monitored and enforced by international organisations, such as the United Nations and regional human rights bodies. These bodies review states' compliance with customary human rights norms and issue recommendations on measures to improve adherence and address violations.
• Treaty interpretation: Customary human rights law can also influence the interpretation and application of treaty provisions, as courts and other adjudicative bodies may refer to customary international law when interpreting a treaty's scope and content in light of the parties' intentions and the object and purpose of the agreement.
• Interaction with treaty law: While customary human rights law operates independently of treaty law, the two sources of law often interact and mutually influence each other. In some instances, customary norms are codified in treaties, while in others, treaties may contribute to the development and consolidation of customary norms by expressing global consensus on certain human rights standards.

How Customary International Law is Determined

Customary International Law is a dynamic and evolving system, and determining its content requires examination of two fundamental elements: state practice and opinio juris. Both elements must be present for a rule to qualify as customary international law:

• State practice (usages or behaviours): This refers to the consistent and general conduct of states, including their actions, decisions, and statements. State practice can manifest itself through various means, such as legislation, executive acts, judicial decisions, diplomatic correspondence, and statements made in international fora.
• Opinio juris (belief that an action is legally required): This element reflects the belief of states that their actions are required by law. To establish opinio juris, it must be demonstrated that states engage in a particular behaviour out of a sense of legal obligation, rather than out of convenience, tradition, or political expediency.

To determine the existence of a Customary International Law rule, the following factors should be considered:

• Consistency of state practice: The behaviour of states should be consistent over time, with few or no deviations. Occasional departures from the general practice may be considered exceptions that can potentially reaffirm the existence of the rule rather than weaken it.
• Generality of state practice: A significant number of states should engage in the practice under consideration, particularly those directly affected by the matter in question. The involvement of major powers and influential states in the practice can be especially persuasive in establishing customary international law.
• Duration of state practice: While there is no set time-frame for the formation of a customary rule, the practice should be long-standing and have persisted for a reasonable period, demonstrating the durability and acceptance of the rule by the international community.
• Evidence of opinio juris: Evaluating the opinio juris of states can be more challenging than ascertaining their practice, as it involves analysing the subjective beliefs of states. Evidence of opinio juris can be found in official statements, resolutions, and declarations, as well as the explanations provided by states for their actions or deviations from a general practice.

Customary International Law is an important component of the international legal framework, reflecting the general practices and beliefs of states in their interactions with one another. Its dynamic nature enables it to adapt and evolve alongside the changing needs and values of the international community, playing an essential role in shaping the global legal landscape and safeguarding human rights across nations.