The United Kingdom has an uncodified constitution, which means it is not all contained in a single document. There are several sources of the constitution, some being written down and some not. The notion that the Constitution of the United Kingdom is unwritten is not strictly correct.
Key principles
The key principles of the constitution are its underlying features. The two most important principles have existed for a very long time, since the creation of Parliament. They were identified by the constitutional lawyer, A.V. Dicey as the twin pillars of the constitution:
European Union membership, the principle that EU law takes precedence over UK law. This principle was famously identified in the Factortame case in which the Merchant Shipping Act 1988 was overturned. This appears to undermine the principle of Parliamentary sovereignty, but Parliament could still withdraw from the EU by repealing the European Communities Act 1972, so in a way Parliamentary sovereignty is preserved.
Sources
There are several sources of the constitution. Not all of the sources are written down (for example, some are contained in conventions), but it is incorrect to say the UK has an "unwritten constitution" because much of it is written down.
For example, in the Constitution of Australia, most of its fundamental political principles and regulations concerning the relationship between branches of government, and concerning the government and the individual are codified in a single document, the Constitution of the Commonwealth of Australia.
Constitutions vary extensively as to the degree of separation of powers, usually meaning the constitutional separation of the executive, legislative and judicial branches of government.
A "constitutional violation" is an action or legislative act that is judged by a constitutional court to be contrary to the constitution, that is, "unconstitutional".
The Constitution of the United States, written in 1787 and ratified in 1789, was the first important written constitution, and a model for a vast number of subsequent constitutional documents.
A constitution may be defined as an organization of offices in a state, by which the method of their distribution is fixed, the sovereign authority is determined, and the nature of the end to be pursued by the association and all its members is prescribed.
Constitution of Poland), and sub-national or provincial (e.g.