The United Kingdom has never had a written constitution embodied in a single document. The foundational constitutional text for what is now the UK is the Magna Carta issued by King John of England in 1215. Since then, the UK's constitution has evolved organically over time in response to political, economic, and social changes.
The present constitution encompasses landmark statutes, such as the Bill of Rights of 1689, as well as many conventions or unwritten rules of constitutional practice. For example, the residual (prerogative) powers of the monarch and the relationship between the monarch and Parliament are still governed largely by these unwritten but nevertheless binding conventions.
Constitutional law in the UK has undergone significant changes during the past 25 years. Key developments include the incorporation of the European Convention on Human Rights into UK law via the Human Rights Act of 1998, the establishment of devolved legislatures in three of the UK's four constituent nations in 1999, a partial reform of the House of Lords in 2000, and the establishment of the Supreme Court (formerly known as the Appellate Committee of the House of Lords) as a separate and independent institution in 2009.
The Scottish independence referendum, held in September of 2014, and the Brexit referendum, held in June of 2016, have strengthened the case for further constitutional reform, with many observers arguing that only a more decentralized, if not a fully federal, system of government can preserve the UK as a unified political entity.
Consult the following secondary sources for information about recent developments in UK constitutional law.
Beyond Magna Carta: A Constitution for the United Kingdom by 
The New British Constitution by 
Constitutional Futures Revisited: Britain's Constitution to 2020 by 
The Changing Constitution (8th ed.) by 
Constitutional Review under the UK Human Rights Act by 
The United Kingdom's Statutory Bill of Rights: Constitutional and Comparative Perspectives by 
Final Judgment: The Last Law Lords and the Supreme Court by 
British Constitution: Continuity and Change by One of the four original copies of Magna Carta from 1215
Public Domain Image via The British Library
Magna Carta Memorial at Runnymede
Donated by the American Bar Association
Photo by Anthony McCallum via Wikimedia Commons
CC BY-SA 4.0 International License
The English Constitution by 
The British Constitution by 
The Constitution of the United Kingdom (3rd ed.) by 
The British Constitution: A Very Short Introduction by 
Constitutional Law, Administrative Law, and Human Rights: A Critical Introduction (6th ed.) by 
British Government and the Constitution: Text and Materials (7th ed.) by To locate additional materials on UK constitutional law from the Georgetown Law Library's collection, use the Advanced Search and select Law Library Catalog.
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