Separation of powers in the United Kingdom

The conception of the separation of powers has been applied to the United Kingdom and the nature of its executive (UK government, Scottish Government, Welsh Government and Northern Ireland Executive), judicial (England and Wales, Scotland and Northern Ireland) and legislative (UK Parliament, Scottish Parliament, National Assembly for Wales and Northern Ireland Assembly) functions. Historically, the apparent merger of the executive and the legislature, with a powerful Prime Minister drawn from the largest party in parliament and usually with a safe majority, led theorists to contend that the separation of powers is not applicable to the United Kingdom. However, in recent years it does seem to have been adopted as a necessary part of the UK constitution.

The independence of the judiciary has never been questioned as a principle, although application is problematic. Personnel have been increasingly isolated from the other organs of government, no longer sitting in the House of Lords or in the Cabinet. The court's ability to legislate through precedent, its inability to question validly enacted law through legislative supremacy and parliamentary sovereignty, and the role of the Europe-wide institutions to legislate, execute and judge on matters also define the boundaries of the UK system.

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