What is the British Constitution?

Why It Matters

A constitution is the body of rules which lays down the relationship between the individual citizen and the state, and between the different parts of the state: government, parliament and the courts.  The powers which the government has to make and enforce laws, and our rights as citizens, are defined by the constitution, which therefore affects us all.


The Essentials


The UK is often said to have an ‘uncodified’ constitution because it has no single written constitutional document. 


Much of the material which makes up the British Constitution is written down in a number of different documents, including within statutes, court judgments, and treaties.


The UK constitution also has unwritten sources, including parliamentary conventions (recorded in Erskine May) and royal prerogatives.


Most people argue that the current constitutional arrangements in the UK reflect the principle of parliamentary sovereignty.  This means that Parliament can change the constitution as it wishes.  Most argue that introducing a codified constitution would contradict the doctrine of parliamentary sovereignty.


There have been a large number of constitutional reforms in Britain in recent times, many of which have taken place on a piecemeal basis and without formal public debate on the long-term implications of such change or consideration of the impact on other elements of the constitution.

The Important Debates

What are the identifiable features of the British Constitution?

It is uncodified and incremental: the British constitution remains a ramshackle construction, which is to be found in statutes, treaties, conventions and other documents, all of which have been pieced together over time and with little coherent ‘purpose’.

It is flexible, and yet there are several features of the British constitution which do not seem easily amendable by Parliament. [More+]

  • It is unitary, but the devolutionary settlements in Scotland, Wales and Northern Ireland may not be easily reversed, and may be leading to further shifts in power from Westminster to the devolved regions. A referendum in March 2011 extended the law-making powers of the Welsh Assembly. In Scotland the current Nationalst Party government has promised to call a referendum on independence. [More+]
  • It is political, in that it is supposed to be Parliament which ultimately determines the shape of the constitution. Arguably it is becoming more ‘legalised’ as the judiciary are required to apply EU law and decide whether some matters are contrary to the Human Rights Act.
  • It is uninterrupted and has largely been the product of incremental, peaceful change. [More+]

Can the Executive make changes to the constitution without public consultation?

  • The new Supreme Court came into being in 2009 following announcements of government policy made in 2003. It was widely assumed at that time that there would be a process of wider public debate, but in fact the changes were introduced relatively rapidly. President of the Supreme Court Lord Phillips has indicated that in extreme circumstances the court could contradict Parliament should the legilature commit to a breach of constitutional principle. Perversely a body whose formation was perhaps insufficiently scrutinised in the public sphere may in future prove to be one of the strongest guardians of the rights of the public against Parliamentary dictat. In considering the enduring uncertainties about the potential remit of the court some former Lords of Appeal have expressed reservations about the potential impact of the ‘law of unintended consequences’.
  • Critics argue that constitutional change should always be legitimised by a referendum. The current administration did call a referendum on the potentialy adoption of the Alternative Vote, however, due to a lack of consultation prior to the referendum, some felt that the wording of the question on electoral reform was not the product of the public will but a political compromise. On the other hand current plans for reform of the House of Lords and the introduction of Fixed Terms for Parliament seem highly unlikely to lead to further referendums. Referendums on a national scale remain infrequent, and see to be chosen for tactical reasons.
  • When Britain joined the EU public debates were largely framed in terms of potential economic benefits and there was little discussion of the question of the UK Parliament ceding powers which, historically, it alone had exercised. The accession to the EU has arguably, therefore, increased the importance of the courts. The legitimacy granted to the EU by the 1975 referendum has continued to shape the agenda long after the terms of the debate evolved.

Is the Constitution relevant?

  • The Constitution shapes the relationship between citizens and those who govern, and between the country’s different governing organs.
  • Legislation which has implications for these relationships is ‘constitutional’. For example proposed legislation to introduce Alternative Voting, in place of First Past the Post, was constitutional in nature since it would have impacted how we choose the individuals who govern us.
  • Constitutional issues are often raised in other contexts and in circumstances where it is not immediately apparent that those issues have a constitutional impact. By way of example the Butler and Chilcot Inquiries, into various aspects of the Iraq war, heard evidence about the informal nature of decision-making under the Blair administration (Butler Inquiry) and the manner in which advice about the legality of invading Iraq was obtained and considered (Chilcot Inquiry).[More+]

How does Europe impact the British Constitution?

  • Britain’s membership of the European Union gives European law primacy over national legislation. If there is a conflict between the two, European law is held supreme. [More+]
  • The task of enforcing European Law is performed not just by the European courts but also by judges and courts at all levels of the national system.
  • Since UK Courts can refuse to enforce UK legislation on the basis that it is incompatible with European law there is a perception or indeed it may be the case that the UK courts have become more powerful.
  • The legal status of British citizens has changed. People in the UK now have the right to address their legal grievances not only at the national level, but also at the European level.

The overarching theme of these changes is Parliamentary Sovereignty. In theory this fundamental feature of the British Constitution remains unchanged. Parliament could pass legislation today withdrawing Britain from the EU and Community law would cease to apply at the national level. On a practical level, however, the implications for Parliamentary Sovereignty are much greater. The social and economic impact of withdrawal renders any such legislation almost inconceivable. As such, it is possible to argue that “for all practical purposes and at least for the foreseeable future, the British Parliament is no longer sovereign.” [More+]

How does the current EU Bill change the situation?

Should the UK reform its constitution?

Constitutional reform is high on the current political agenda, and reforms were promised in the manifestos of all three main political parties.  Proposals for reform to each element of the Constitution, e.g. House of Lords, the Electoral Process etc., are considered in the relevant sections of this website. See also ‘Do we need a written constitution?’.


Magna Carta


Union with Wales


Charles I dismissed Parliament, then subsequently recalled it in order to raise taxes


Parliament formed a committee of grievance and presented a Petition of Right to the king to protect subjects from further taxation unauthorised by Parliament


Parliament passed the Three Resolutions: 1. They would condemn any move to change the established religion 2. They would condemn taxation levied without parliament’s authority 3. They declared that Merchants paying ‘illegal’ taxes betrayed the Liberty of England


Oliver Cromwell elected to Parliament for the 2nd time


Outbreak of the Civil war


Charles I surrenders


The Rump Parliament gave parliament the right to make laws without the king’s approval


Charles I executed


Parliament abolishes the monarchy


Cromwell chairs the New English Commonwealth


Oliver Cromwell is elected Lord Protector of the Commonwealth


Oliver Cromwell dies and appoints his son, Richard, as his successor


Richard Cromwell resigns


General Monck marches to London, dissolves Parliament and Charles II is invited to resume the throne (‘the Restoration’)


Charles II dies and is succeeded by his brother James II, a catholic


James II overthrown in the ‘Glorious Revolution’


William and Mary invited to become joint sovereigns


Enactment of the Bill of Rights


Union with Scotland


Union with Ireland


(Also 1867, 1872) Reform Acts-extended voting rights and established the secret ballot


Parliament Act


Reform Act-ended property qualifications for men


Anglo-Irish Treaty signed-removes 26 Counties of Irish Free State from UK


Reform Act-gave equal voting rights to women


Parliament Act


European Communities Act


Human Rights Act


Scotland Act


Government of Wales Act


House of Lords Act


Greater London Act


Freedom of Information Act


Constitutional Reform Act


Government of Wales Act


Opening of the Supreme Court

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