By Law Teacher

2.2.1 Sources of the Constitution – Introduction

Welcome to the third lesson of the second topic in this module guide – Sources of the Constitution! With so many rules from a variety of sources, the UK constitution can be defined as uncodified. The absence of any formal codification makes ‘constitutional’ sources quite unclear. An important aspect in understanding the UK constitution is to understand how a variety of sources can be described as constitutional, in both the legal and non-legal sphere.

At the end of this section, you should be comfortable being able to outline the main sources of the UK constitution. This section begins by further elucidating the uncodified nature of this constitution and outlining the main sources. These sources are then elaborated upon, with a discussion of the constitutional nature of: Acts of parliament; the common law; European law; international law; and constitutional conventions. The discussion is then concluded with a brief look at the hierarchy of constitutional sources.

Goals for this section:

  • To be able to outline both the legal and non-legal sources of the UK constitution.
  • To understand how, in an uncodified constitution, a variety of sources can take on a constitutional dimension.

Objectives for this section:

  • To understand how and which acts of parliament may assume a constitutional importance.
  • To appreciate the ways in which common law principles become constitution, and how judicial precedent can affect this.
  • To be able to explain how European and international law can affect the constitutional makeup of the UK.
  • To appreciate which non-legal sources are constitutional, and in particular how constitutional conventions can provide rules which are not legally binding, but which still act as constraints.
  • To appreciate the hierarch of constitutional sources.

2.2.2 Sources of the Constitution Lecture

The United Kingdom does not have a single document known as the ‘Constitution’ and as such, its constitution is not codified. In fact, no constitution globally is contained within a single document; even ‘written constitutions’ are merely a starting point for the full body of constitutional law, which elaborates upon the countries governance structure. Written documents might offer fundamental constitutional principles, but there are further texts which supplant and elaborate upon the basic principles.

Ordinary legislation is drafted in order to provide fuller information about those basic principles which are stated in the constitution. In a common law system, the courts also interpret the statutory legislation by clarifying points of law which require interpretation. Judicial precedent in England and Wales binds lower courts and creates a series of judicial decisions which itself can be considered a source of constitutional law. Finally, informal resolutions between parties in constitutional matters can be made where there is no legislative solution to an issue. Constitutional conventions or political precedents can be created in this way when relevant parties show evidence of being willing to adhere to the resolution to the issue.

The UK’s absence of a written constitution makes the scope of the sources, which would be correctly labelled as ‘constitutional’ less clear-cut than a situation where there is a codified constitution.The disadvantage of this lack of clarity can be highlighted by the legal protection of civil liberties and human rights prior to the Human Rights Act 1998 where no comprehensive enforceable Code or Bill of Rights.

In order to understand the United Kingdom’s constitution, which is largely unwritten, it is necessary to consider a number of legal and non-legal sources.

(a) Acts of Parliament

Members of the House of Commons (elected) and of the House of Lords (unelected) approve statutes, which are drafted by government lawyers and scrutinised by the two Houses during the legislative process. A large proportion of the UK’s statutory arrangements are now laid down in statutes. A great deal of legislation is concerned with the allocation and organisation of power to, the institutions of government.

In 2003, the Joint Committee on the Draft Civil Contingencies Bill drew up a list of statutes, which were considered to be fundamental elements of constitutional law. The first of these statutes was the Magna Carta 1297, which proclaims that punishment must be prescribed by law and that individuals should not be denied justice. In Thoburn v Sunderland City Council (2003) Laws LJ defined constitutional statutes as those which condition the legal relationship between the citizen and the state in some general overarching matter; or which contribute in some way to fundamental constitutional rights. He went on to list a number of other constitutional statutes.

Several of these Acts have now been amended or repealed. There are also a number of Acts which have been passed through Parliament since 2003 that have constitutional status.

(b) The Common Law

Another important source of the United Kingdom’s constitutional rules can be found within the law reports, which report on the important judicial decisions made within the court system. Judges in England and Wales, Scotland and Northern Ireland have all contributed to the development of constitutional principles within the UK.

The principle role of courts is in the application of the facts of a case to the law and resolving disputes between litigants. However, judicial precedent is more complicated than this; cases with a constitutional dimension to them are capable of making public law. Judicial precedent is a source of constitutional law in three senses:

  • Firstly, in the interpretation of constitutional legislation; legislation may be clear or unspecific or not cover a specific set of facts. Courts are able to expand legislation, or the meaning of particular terms in legislation to apply to a specific set of facts that are not covered within the statutory language.

    In YL v Birmingham City Council [2007] UKHL 27, [2008] 1AC 95, Lord Neuberger held that a statute had to be interpreted by the judge in line with what they believe that Parliament was trying to achieve. There are clearly cases where courts are required to carry out the interpretation of statutes by filling in the gaps in order to deal with constitutional matters. The law is inevitably influenced by the judges’ views on what the law should be.

  • The second role of the courts in a common law system in relation to the constitution is the creation of a body of judge-made law. Much of the civil law is based upon the common law, which are legal principles, which are expressed by the judges on a case-by-case basis. In situations where government Ministers express discretionary powers, the Minister is required to act in accordance with certain principles of good administration. There are general principles, which have been developed via the common law that apply generally to the decisions of public bodies. Such principles are enforced through the process of Judicial Review, and can be challenged within the courts.

    Common law constitutional principles are also a judge-made source of public law. The principle of legal certainty is an example of such a principle. Courts will attempt to interpret legislation in accordance with the principle of legal certainty. Although Parliament is considered to be sovereign and judges ought not overrule the will or Parliament, this raises the question as to whether if a statute clearly conflicts with a fundamental principle, how should it be interpreted by the courts.

  • Finally, the royal prerogative is considered to be part of the common law, in that it authorises the executive branch of government to carry out certain acts such declaring war, or granting honours. It is a historical legacy that reflects the monarch’s previous role as assigning directions to Parliament on the countries governance. Much of this legacy has now been removed through legislation; such powers are now exercised by government Ministers on behalf of the monarch.

(c) European Law

The United Kingdom has been a member state of what is now known as the European Union since 1973; executive, legislative and judicial decision in many policy areas are currently made through or are influenced by European Union institutions. European Union law is currently incorporated into UK law by sections 2 and 3 European Communities Act 1972.

EU membership changed what was possibly the most basic rule of the UK constitution. In Case 6/64 Falminio Costa v ENEL [1964] ECR 585 the court of the European Economic Community (the forerunner to the European Union) held in a landmark decision that European Community law has supremacy over national law. This ruling then changed a fundamental rule of constitutional systems, that of Parliamentary sovereignty. The impact of this ruling was first experienced in the UK in R v Secretary of State for Transport, ex parte Factortame Ltd. and ors (No.1) [1990] 2 AC 85, when Spanish owners of fishing vessels argued that they had been discriminated against on the ground of nationality and the courts were asked to suspend the Merchant Shipping Act 1988.

Further, in Thorburn v Sunderland City Council (2003) Laws LJ held that rights and freedoms afforded under EU law will prevail over express terms of UK law, including Acts of Parliament passed after the coming into force of the European Communities Act 1972, even when EU law in clearly inconsistent with the Act of Parliament. Section 18 European Union Act 2011 states “Directly applicable or directly effective EU law (…) falls to be recognised and available in law in the United Kingdom only by virtue of that Act or where it is required to be recognised and available in law by virtue of any other Act’. This provision makes clear that EU law takes effect subject to the will of Parliament.

Under section 2 Human Rights Act the UK courts are obliged to take into account all decisions of the European Court on Human Rights when considering a claim involving section 1 and Schedule 1 (most of the substantive rights from the European Convention) Human Rights Act 1998. The implication of this is that it means that post 1998 decisions, such as those on proportionality, have become a part of UK constitutional and administrative law.

(d) International Law

International Treaty law can have an influence on and is sometimes a source of constitutional law. International and bi-lateral treaties are often given effect within UK domestic law. In more recent years, transnational institutions, such as the United Nations, and treaty law, are increasingly influencing what happens within national constitutional systems. Since the end of the Second World War, a wide body of international human rights agreements have also been established, with monitoring bodies that implement the terms of each major agreement. States domestic laws cannot supersede these rights.

There are two main sources of international law: treaties and customary international law. Treaty law is an agreement under international law, usually between states, but international organisations can also be subjects of international law. The Vienna Convention on the Law of Treaties 1969 provides the internationally accepted rules on treaty interpretation and states that a treaty should be in writing.

(e) Constitutional Conventions

There are many important constitutional matters in the UK for which no law exists. In such instances, it is necessary to resort to non-legal constitutional sources, also known as constitutional conventions. AV Dicey in Introduction to the Study of Law of the Constitution (1885) distinguishes between law and conventions. Laws are enforceable in the courts. There are no judicial remedies or penalties if conventions are violated.

In such circumstances, legal freedom is constrained by political precedent. Although there is no law to give it effect, there is a clear and long standing political precedent or constitutional convention that a certain rule must be followed. Such rules are not found uniquely in systems like the UK that are missing a written constitution; they can also play a similar role in elaborating upon the rules within a codified constitution.Such rules are established through habitual and customary practices within government although in recent years these conventions have been codified and formalised in a gradual manner.

How are conventions created?

  • Dicey stated that constitutional conventions are the ‘morality’ of the constitutions and defined them as ‘understandings, habits or practices’ that ‘regulate the conduct of the several members of the sovereign power, of the Ministry or other officials’ (Dicey, An Introduction to the Law of the Constitution, London, 1959: p.24).
  • Conventions are established through precedent, so there must be a record of conventions being followed for a period. Conventions give effect to underlying constitutional principlesDemocracy is the constitutional principle, which underlies the constitutional convention that the monarch should request the party commanding a majority after a general election to form a government.
  • The Jennings Test: Ivor Jennings, The Law and the Constitution University of London Press, 1963, p.163. The test purports to determine whether a political practice or rule can be correctly regarded as a constitutional convention, it states;
  • (i) What are the precedents?
  • (ii) Did the relevant actors believe themselves to be bound by the rule?
  • (iii) Is there a rationale for the rule?
  • In general, constitutional conventions are binding political rules. Some authors have distinguished between binding and non-binding conventions.

Why are constitutional conventions observed?

  • People might abide by rules based on their own sense of morality, or because the majority of people respect a certain system of rules. People also chose to abide by rules because of the stigmatising effect of breaching societies norms.
  • The reasons why people obey rules helps us to understand why people obey constitutional conventions. All important constitutional conventions are simply a practical application of fundamental constitutional principles, which are by definition widely accepted and deeply rooted. Further, constitutional actors may not personally agree with a particular principle underlying a convention, but since a majority of people seem to agree with it, they are inclined to accept the majority view. Actors may also respect constitutional rules for self-serving reasons. Politicians in government may choose to abide by conventional rules for fear that the failure to do so would incline opposition politicians when in power to do likewise. The prescriptive nature of constitutional conventions does not derive from legal rules, but from morality, a wish to adhere to a majority view and through self-interest.
  • Conventions are not always respected, like legal rules, they may be breached, however this breach may not lead to any significant consequences. The breach of some conventions might have quite significant consequences.
  • Although conventions themselves are not legally enforceable, they are on occasion turned into law through the enactment of legislation.
  • Although constitutional conventions are not legally enforceable, certain case law suggests that conventions are not wholly legally irrelevant. A convention can influence the application of the law to the facts of a case.

f) Hierarchy of Constitutional Sources

Constitutions are usually regarded as the highest form of law in a country; written constitutions are nearly always hierarchically superior to other forms of legislation. This means that all other legislation has to accord with the principals of the constitution and that judges are able to strike down any legislation, which is found to be unconstitutional. In France, the judges refer codified laws back to the legislature for further consideration if it is found to be unconstitutional.

2.2.3 Sources of the Constitution Lecture – Hands on Examples

The following scenario aims to test your knowledge of the Sources of the UK Constitution. The answers can be found at the end of this section. Try to apply the law to the facts and think about the various topics that have been covered in the module.

Do not be worried if the answer is not immediately obvious, problem questions require you to understand and to apply the law as opposed to just learning and repeating what you have learned. The answers are also just for guidance purposes; you can still show understanding of the topic in various ways. Refer back to the notes if necessary, this should help you understand how the various constitutional sources in the UK and the distinctions between legal sources and political sources.


Part A:  The UK government introduces a number of new pieces of legislation into Parliament as a result of the leave vote to leave the European Union. The Brexit Act 2016 removes all references to EU law in the legal system of England and Wales. The Anti-Brexitism Act 2016 criminalises individuals from referring to others as ‘Brexiters’ or ‘Remainers’ in a public place, or via social media. The Scotland Remains in the EU Act 2016 grants Scotland independence from the UK in order to enable Scotland to stay in the European Union. Which if any of these Acts of Parliament are constitutional acts and why?

Part B: Le Doso is a ‘monist’ state in relation to international treaty law. They have just ratified the International Convention on the Protection of Rights of All Migrant Workers and Member of Their Families 1990. A group of workers who have travelled from a neighbouring state of Las Pasos have worked in Le Doso for 10 months on a government project to build railways; they feel that they have been discriminated against in relation to the terms and conditions offered to them and the Las Pasos nationals. How can they enforce their rights under the Migrant Workers Convention? How would this be different if Le Doso was a ‘dualist’ system that had not passed any legislation specifically passing the Migrant Workers Convention into law?

Part C: Following the vote to leave the EU and the difficulties in agreeing how the UK will leave the EU, Theresa May decides to resign as Prime Minister for the United Kingdom and approaches the Queen with her resignation. The Queen decides to approach Nigel Farage leader of the UK Independence Party to form a government although they do not command a majority in the House of Commons. The Queen likes the work they did during the campaign to leave the EU and thinks they ought to have a chance in government. Taking account of constitutional conventions and common law, what is the likely outcome of the Queen’s actions?

Part D: Public pressure leads the Conservative Party to call an early general election in 2018, the Labour Party win the election with Jeremy Corbyn as leader who wants to introduce a financial policy referred to as ‘Quantitive Easing’ in order to inject money into the economy and to raise funds to renationalise the railways. The Labour government introduce the Quantitive Easing Bill 2018, which is defined as a ‘money bill’ into Parliament for debate, the House of Lords who still command a Conservative majority and who don’t agree with the nationalisation of the railways block the Bill. What is the constitutional solution for the Labour Government?

Suggested Answers

A) In the absence of a written constitution a key source of UK constitutional law is Acts of Parliament which deal with constitutional law issues. The proposed Brexit Act 2016 removes references to European Union law from the English/Welsh legal system – since European Union law is currently part of the body of UK constitutional law, this Act is an amendment to the UK constitution and thus a constitutional act. The Anti-Brexitism Act 2016 establishes criminal laws which have an impact on everyone and as such do not form part of the UK constitution. The Scotland Remains in the EU Act 2016 grants Scottish independence and hence changes the relationship between the Westminster government and the Scottish government in a fundamental manner. It is a major constitutional change and as such this is a constitutional Act.

B) A ‘monist’ system in respect of international law means that once an international Convention is ratified it automatically becomes law in that country and needs no further action from the legislature to bring it into law. The Las Pasos migrant workers should be able to rely upon anti-discrimination measures within the Migrant Workers Convention to bring their claim to a Le Doso court. If Le Doso were a dualist state, it means that it requires legislation to bring international obligations into domestic law. Since Le Doso have not introduced legislation to give effect to the Migrant Workers Convention, the Las Pasos migrant workers would only be able to rely upon any existing legislation in force in Le Doso to bring their claim. [NB: If an international convention has a individual claims procedure this is also a possible avenue of redress, but not strictly required for a question on constitutional law].

C) At common law, under the Royal Prerogative, the reigning Monarch has unlimited power to appoint the Prime Minister. However, it is a constitutional convention that the Government must have been elected in a general election and command a majority in the House of Commons. The UK Independence Party do not have a majority in the House of Commons, so the Queen is unable to appoint Nigel Farage as Prime Minister. There is no legal sanction against the Queen in this instance, but such an act is likely to bring the Monarch into question or even challenge the existence of the Monarchy and the Monarch’s role as Head of State.

D) Since the Parliament Act 1911 the House of Lords have no power to veto a Bill, except one to extend the lifetime of Parliament. It placed strict limits on the House of Lord’s involvement in financial decisions. By convention, money bills have expedited passage through the House of Lords with little debate