By using this site, you agree we can set and use cookies. OK For more details of these cookies and how to disable them, see our cookie policy.
Magna Carta
Britain's unwritten constitution
Article written by:
Robert Blackburn
Magna Carta today
13 Mar 2015
Unlike most modern states, Britain does not have a codified constitution but an unwritten one formed of Acts of Parliament, court judgments and conventions. Professor Robert Blackburn explains this system, including Magna Carta’s place within it, and asks whether the UK should now have a written constitution.
For most people, especially abroad, the United Kingdom does not have a constitution at all in the sense most commonly used around the world – a document of fundamental importance setting out the structure of government and its relationship with its citizens. All modern states, saving only the UK, New Zealand and Israel, have adopted a documentary constitution of this kind, the first and most complete model being that of the United States of America in 1788. However, in Britain we certainly say that we have a constitution, but it is one that exists in an abstract sense, comprising a host of diverse laws, practices and conventions that have evolved over a long period of time. The key landmark is the Bill of Rights (1689), which established the supremacy of Parliament over the Crown following the forcible replacement of King James II (r. 1685–88) by William III (r. 1689–1702) and Mary (r. 1689–94) in the Glorious Revolution (1688).
From a comparative perspective, we have what is known as an ‘unwritten constitution’, although some prefer to describe it as ‘uncodified’ on the basis that many of our laws of a constitutional nature are in fact written down in Acts of Parliament or law reports of court judgments. This aspect of the British constitution, its unwritten nature, is its most distinguishing characteristic.
The Bill of Rights
This declaration of 1689, known as the Bill of Rights, stated that it was illegal for the Crown to suspend or dispense with the law, and insisted on due process in criminal trials.
View images from this item  (3)
Usage terms © Parliamentary Archives, London HL/PO/JO/10/1/1430, membrs. 2–3
Held by© Parliamentary Archives, London HL/PO/JO/10/1/1430, membrs. 2–3
Features of Britain’s unwritten constitution
Another characteristic of the unwritten constitution is the special significance of political customs known as ‘conventions’, which oil the wheels of the relationship between the ancient institutions of state. These are unwritten rules of constitutional practice, vital to our politics, the workings of government, but not committed into law or any written form at all. The very existence of the office of Prime Minister, our head of government, is purely conventional. So is the rule upon which he or she is appointed, being whoever commands the confidence of the House of Commons (the majority party leader, or head of a coalition of parties).
The Monarchy is one of the three components of Parliament (shorthand for the Queen-in-Parliament) along with Commons and Lords. In legal theory, the Queen has absolute and judicially unchallengeable power to refuse her assent to a Bill passed by the two Houses of Parliament. However, convention dictates the precise opposite and in practice she automatically gives her assent to any government Bill that has been duly passed and agreed by Parliament. Another important convention is that government ministers must have a seat in Parliament (and, in the case of the Prime Minister and Chancellor of the Exchequer, specifically in the House of Commons) in order to hold office. This is a vital aspect of what is known as the ‘Westminster system of parliamentary government’, providing a direct form of executive responsibility and accountability to the legislature.
The written documents of our unwritten constitution
There is irony in the fact that the United Kingdom today does not have a written constitution, yet historically it has had a rich heritage of pioneering constitutional charters and documentation. First and foremost is Magna Carta (1215), the ‘Great Charter of the Liberties of England’. This established the principle that our rulers, at that time the king, could not do whatever they liked, but were subject to the law as agreed with the barons they governed. This simple concept laid the foundations for constitutional government and freedom under the law. Insofar as Magna Carta was ‘the first great public act of the nation’, it also established the direction of travel for our political system towards representative institutions and, much later, democracy itself.
Magna Carta 1215
One of the four surviving copies of the 1215 Magna Carta containing the famous clause ‘to no one will we sell, to no one deny or delay right or justice’.
View images from this item  (1)
Usage terms
Public Domain in most countries other than the UK.
In 1258, the Provisions of Oxford, sometimes referred to as the first ever written constitution, provided for a Council of twenty-four members through whom the King should govern, to be supervised by a Parliament. This was convened for the first time in 1264 by Simon de Montfort (d. 1265). During the constitutional conflicts of the 17th century, the Petition of Right (1628) relied on Magna Carta for its legal basis, setting out rights and liberties of the subject including freedom from arbitrary arrest and punishment. The Bill of Rights (1689) then settled the primacy of Parliament over the monarch’s prerogatives, providing for the regular meeting of Parliament, free elections to the Commons, free speech in parliamentary debates, and some basic human rights, most famously freedom from ‘cruel or unusual punishment’. This was shortly followed by the Act of Settlement (1701) which controlled succession to the Crown, and established the vital principle of judicial independence.
Image of the House of Commons, from True Platforme and Manner of the Sitting in the Lower House of Parliament
This is the earliest representation of the House of Commons. It is unlikely to be accurate in all its details, but it gives an impression of the tall, narrow and cramped chamber in which the House met.
View images from this item  (1)
Usage terms Public Domain
The Petition of Right
The Commons asserted their interpretation of the law by presenting Charles with a ‘Petition of Right’, rather than a formal bill, implying that they were claiming the subject’s existing rights, rather than creating new ones.
View images from this item  (1)
Usage terms © Parliamentary Archives, London HL/PO/PU/1/1627/3c1n2
Over the past century there have been a number of Acts of Parliament on major constitutional subjects that, taken together, could be viewed as creating a tier of constitutional legislation, albeit patchy in their range and with no special status or priority in law. They include:
The Parliament Acts (1911–49) that regulate the respective powers of the two Houses of Parliament.
The Representation of the People Acts (1918) (as amended) providing for universal voting and other matters of political representation.
The European Communities Act (1972) making the UK a legal partner in the European Union.
The Scottish, Welsh and Northern Ireland devolution Acts of 1998 (as amended) creating an executive and legislature for each of those three nations in the UK.
The Human Rights Act (1998) establishing a bill of rights and freedoms actionable by individuals through the courts.
Recently, too, some conventions have been subject to an ad hoc codification, such as the principles of ministerial responsibilities in the Ministerial Code.
Human Rights Act 1998
The purpose of the Human Rights Act was to incorporate into UK law the rights and freedoms guaranteed under the European Convention on Human Rights (1953).
View images from this item  (1)
Usage terms Crown Copyright
Should the UK have a written constitution?
The question then arises in this 800th anniversary year – should the UK now take steps to codify all its laws, rules and conventions governing the government of the country into one comprehensive document, ‘a new Magna Carta’? The case for a written UK constitution has been debated at our universities and by politicians of all parties for several decades and has been the subject of a House of Commons committee inquiry during the 2010–15 Parliament. If a written constitution for the future is to be prepared, it must be one that engages and involves everyone, especially young people, and not simply legal experts and parliamentarians. Some of the mystique and charm of our ancient constitution might be lost in the process, but a written constitution could bring government and the governed closer together, above all by making the rules by which our political democracy operates more accessible and intelligible to all.
Written by Robert Blackburn
Robert Blackburn (LLD, FRHistS) is Professor of Constitutional Law at King’s College London. He has published many books on political and constitutional affairs, among them The Electoral System in Britain (Macmillan, 1995), Fundamental Rights in Europe (OUP, 2001), Parliament (2nd ed., Sweet & Maxwell, 2002) and King and Country (Politico’s, 2006). He is a member of the Magna Carta 800th Anniversary Committee.
The text in this article is available under the Creative Commons License.
See Also
Magna Carta and human rights
Magna Carta and jury trial
Why Magna Carta still matters today
Magna Carta in the modern age
Human rights legislation
800 years of Magna Carta
The legal significance of Magna Carta today
Related Collection Items
The Bill of Rights
Magna Carta 1215
Image of the House of Commons, from True Platforme and Manner of the Sitting in the Lower House of Parliament
The Petition of Right
Human Rights Act 1998
Related Teaching Resources
Should we remember Magna Carta?
Magna Carta, parliament and representation of the people
External links
The British Library is not responsible for the content of external Internet sites..
Magna Carta: My Digital Rights
The Magna Carta Project
Magna Carta
Collection items
Teaching resources
Supported by
About Us
About the British Library
Opening times
Press Office
Jobs and opportunities
Freedom of Information
Support Us
Make a donation
Become a Patron
Explore Business Partnerships
Quick Links
My account
My Reading Rooms requests
British Library On Demand
Digitisation Services
Images Online
Venue Hire
Collection Metadata
Information for
Research Collaboration
Desktop site
Terms of Use
About the British Library
Contact Us
All text is © British Library and is available under Creative Commons Attribution Licence except where otherwise stated
Skip to main content
Catalogues & CollectionsSearch the Main CatalogueArchives and ManuscriptsSound and Moving ImageBritish National BibliographyAll Catalogues >Business and ManagementDigitised ManuscriptsSocial WelfareSoundsTheses (EThOS)Web ArchiveAll Digital Collections >Register for a Reader PassOnline help to use our collectionsUsing our Reading RoomsUsing the Main CatalogueOverview of the CollectionOrder Copies of DocumentsOrder Images from the CollectionDiscover & LearnSchools and TeachersAdultsFamilies and Community GroupsOnline ResourcesLearning at the Library >Discovering Literature Discovering Children's BooksDiscovering Sacred TextsBritish Accents and DialectsMore Online Exhibitions > <img src='/britishlibrary/~/media/bl/global/dl%20childrens%20literature/collection%20items/tiger-tea-7-stories-jk_03_01_02_01_(2).jpg?w=96&amp;h=96&hash=4C1C22772A3CB29F5120AF8035CFD9EE' alt='The Tiger Who Came to Tea by Judith Kerr sketches and original artwork' /> The Tiger Who Came to Tea by Judith Kerr: sketches and original artwork <img src='/britishlibrary/~/media/bl/global/dl%20childrens%20literature/collection%20items/seans-red-bike-by-x_990_7325_fc.jpg?w=96&amp;h=96&hash=A4E82AF332EC9FB5FD8D1EA4EE6130CD' alt='Sean&#39;s Red Bike by Petronella Breinburg, illustrated by Errol Lloyd' /> Sean's Red Bike by Petronella Breinburg, illustrated by Errol Lloyd What’s OnExhibitionsFree EventsPast Event RecordingsTalks and DiscussionsAdult CoursesToursAll Events >MembersSchools and CollegesBusiness PeopleFamilies <img src='/britishlibrary/~/media/bl/global/whats%20on/exhibitions/unfinished%20business/unfinished-business1.jpg?crop=1&amp;cropX=9&amp;cropY=2&amp;cropW=890&amp;cropH=500&amp;cropcachekey=192890500&amp;w=224&amp;h=126&amp;dispW=224&amp;dispH=126&hash=B063E407F6BC94812E3E407EE4D870C6' alt='A graphic of people with placards expressing feminist demands.' /> Unfinished Business: The Fight for Women's Rights The fight for women’s rights is unfinished business VisitFull Opening Times > <img src='/britishlibrary/~/media/bl/global/navigation/visit/how-to-get-there.jpg?w=96&amp;h=96&hash=A16074F95D7F1FF92A7BB1E6DA0B9CA6' alt='How to get there' /> How to Get Here <img src='/britishlibrary/~/media/bl/global/navigation/visit/keeping%20you%20safe_-96x96.jpg?w=96&amp;h=96&hash=B17CAB2BCD70C81A21CB08C9796EF894' alt='Good to go logo' /> Keeping everyone safe <img src='/britishlibrary/~/media/bl/global/navigation/visit/reading-rooms.jpg?w=96&amp;h=96&hash=CF31B79062822F83C17D341F053B8C7B' alt='Reading rooms' /> Reading Rooms <img src='/britishlibrary/~/media/bl/global/navigation/visit/exhibitions-events.jpg?w=96&amp;h=96&hash=F2ED2F985E2CE4AD4988A6C373F902DB' alt='Exhibitions and events' /> Exhibitions & Events <img src='/britishlibrary/~/media/bl/global/navigation/visit/facilities-and-access.jpg?w=96&amp;h=96&hash=A081F2745B69F502C30453D6C0649452' alt='Facilities and access' /> Facilities <img src='/britishlibrary/~/media/bl/global/navigation/visit/food-and-drink.jpg?w=96&amp;h=96&hash=5A15C3A8B8328B8C1A9A2C5C6FB97A8C' alt='Food and drink' /> Eat, Drink, Shop <img src='/britishlibrary/~/media/bl/global/navigation/visit/school-visits.jpg?w=96&amp;h=96&hash=FE22CF4366FF610467B86C4EFA797AB6' alt='School visits' /> School Visits <img src='/britishlibrary/~/media/bl/global/navigation/visit/library-registration.jpg?w=96&amp;h=96&hash=96FACC9D3F2C770E9B183808EE4A5FDC' alt='Library registration' /> Register for a Reader Pass Business & IP CentreWorkshops and EventsWebinarsAdvice ClinicsInnovating for GrowthFind a Centre Near YouStart ups in London LibrariesBusiness and Management PortalFree Industry and IP GuidesDatabases and PublicationsErasmus ProgrammeResearch ServiceBusiness BlogAbout UsBusiness & IP Centre >Business plan FAQHow to start a business from scratchWhat is intellectual property?Why you need to protect your intellectual propertyMore business articles >Visit the ShopAccessoriesApparelCards and PostcardsFood and DrinkFun and GamesHomewareJewelleryStationeryTechAlice in WonderlandBook LoversLiterary LondonLove LibrariesMap LoversThe Wonderful Wizard of OzTreasures of the British Library <img src='/britishlibrary/~/media/bl/global/navigation/fiction%20342%20web%20header%20cropped.jpg?crop=1&amp;cropX=0&amp;cropY=0&amp;cropW=1591&amp;cropH=895&amp;cropcachekey=1001591895&amp;w=224&amp;h=126&amp;dispW=224&amp;dispH=126&hash=87C0EEC2E75718A35AEA81C0A52D4FAE' alt='Get 3 for 2 on all British Library Fiction' /> Get 3 for 2 on all British Library Fiction JoinBecome a ReaderBecome a MemberBecome a Patron <img src='/britishlibrary/~/media/bl/global/join/join-images_reader.jpg?crop=1&amp;cropX=0&amp;cropY=0&amp;cropW=304&amp;cropH=171&amp;cropcachekey=100304171&amp;w=224&amp;h=126&amp;dispW=224&amp;dispH=126&hash=27C3B87778DA8C8B3DF856F57D13D711' alt='Reader image for the Join page at the British Library' /> Become a Reader <img src='/britishlibrary/~/media/bl/global/join/join-images_member.jpg?w=224&amp;h=126&hash=37176DA5846C177519F2599249931D39' alt='Members image for the British Library' /> Become a Member <img src='/britishlibrary/~/media/bl/global/join/join-images_patron.jpg?w=224&amp;h=126&hash=A2F65B1B465B25BA8E6777D26FFD64AB' alt='Patron image for Join page at the British Library' /> Become a Patron
Home Themes Articles Collection items Videos People Teaching resources