The United Kingdom Constitution

A Written or Unwritten Constitution?

The United Kingdom is often said to be a country without a written constitution.  This is not strictly true.  Although there is no single codifying document, such as the United States or France have, more than half of the British constitution is written down, mainly in statutes and case law.  Other aspects of the constitution are found in non-binding conventions, parliamentary rules, and the royal prerogative.  These various sources make it difficult to pinpoint specifics of the constitution, but on the other hand allow for the constitution to be easily amended, giving it a flexible nature.  Traditionally, the UK constitution is said to be founded on two principles:  the doctrine of parliamentary supremacy and the rule of law.

Parliamentary Supremacy

Parliament is the supreme law-making body.  This means that it has complete sovereignty to make or unmake any law that it wishes to.  This contrasts with other jurisdictions, such as the United States, whose laws may often be challenged as being unconstitutional.  Consequently, Parliament is not bound or subject to any other government or state authority, including the courts.  This position has now changed, however, following the United Kingdom’s accession to the European Union in 1972, and EU law now takes precedence over that of the UK where there is a conflict between the two. 

The Rule of Law

Although the concept of the rule of law differs from one jurisdiction to the next, it basically means that the law is above every citizen and is applied to every citizen equally.  Although no precise definition of ‘the rule of law’ exists, certain elements are seen as essential, such as that laws should be published, or that the judiciary should be independent.  Of particular importance in the concept of the rule of law is that the government itself should be restrained in its governance and government officials held accountable for their actions.  Of course, dictatorships or military juntas may look upon the rule of law in a different light.    

Constitutional Monarchy and the Royal Prerogative

The United Kingdom is a constitutional monarchy, meaning that it has a monarch as head of state.  Nowadays, the monarch’s role is largely ceremonial and reserved to duties such as the State Opening of Parliament.  The day-today running of the country is left to the prime minister and the heads of the various ministries of state.  Nevertheless, the monarch does retain some powers, known as the royal prerogative, which are generally exercised upon the advice of the prime minister or other ministers.  One of the most important of these is the power to appoint or dismiss prime ministers.  The last time this particular power was used was in 1974 when Her Majesty Queen Elizabeth II appointed Harold Wilson as prime minister even though he did not command a majority in the House of Commons.  The appointment was made upon advice from the Privy Council.  Other powers under the royal prerogative include the power to make war and peace, the power to issue passports, and the power to appoint bishops and archbishops of the Church of England.

Sources of Constitutional Law

As mentioned, the constitution in the UK is derived from several sources.  One of the most important is Acts of Parliament.  The Parliament Acts of 1911 and 1949, for example, allow the House of Commons, in certain limited circumstances, to pass legislation without the consent of the House of Lords, and consequently to act in a manner which would otherwise be unconstitutional.  This is very rare, however, and has happened less than five times in the last sixty years.  The threat of using the Parliament Acts may be sufficient to pass legislation which is unpopular in the House of Lords. 

Case law also forms an important part of the constitution.  The decisions of the judiciary have occasionally imposed limits on executive power.  Constitutional conventions, although not legally binding, also play an important role in the UK’s legal fabric.  By convention, the monarch appoints as prime minister the person who commands a majority in the House of Commons after a general election.  By law, however, there is nothing to stop the monarch from appointing his or her head gardener as prime minister.  This would never happen, of course, but in strict legal theory remains a possibility.   

Finally, EU law and international treaties may also contribute to the UK’s constitution.  In fact, in one case concerning EU law the House of Lords went so far as to grant an injunction to ‘disapply’ a legitimate Act of Parliament.  Again, this is an extremely rare occurrence, and decisions affecting the constitution are not taken lightly.


The Labour government which came to power in 1997 has made several significant changes to the UK’s constitution.  The most notable of these have been the creation of the Welsh Assembly and the Scottish Parliament.  The main powers that have been delegated include those regarding health and education.  Other more serious powers, such as those on defence, remain the sole preserve of Westminster.