Constitution of the United Kingdom from the state, which was confirmed by the Church of Scotland Act 1921. England and Wales share the same legal system, while Scotland and Northern Ireland each have their own distinct systems. These distinctions arose prior to and were retained after the unions according to the terms of the 1706 Treaty of Union, ratified by the 1707 Acts of Union, and the Acts of Union 1800. Reforms since 1997 have decentralised the UK by setting up a devolved Scottish Parliament and assemblies in Wales and Northern Ireland. The UK was formed as a unitary state, though Scotland and England retained
Citation of United Kingdom legislation (OS); before that date, legislation was passed either by the Parliament of England or the Parliament of Scotland. Acts passed by each of these parliaments, except for the Parliament of Scotland, are cited in the same way as pre-1963 Acts of the Parliament of the United Kingdom; i.e., by parliamentary session and chapter number. Acts passed by the Parliament of Scotland are cited by calendar year and chapter number. Note also that Acts of the last session of the Parliament of Great Britain and the first session of the Parliament of the United Kingdom are both cited as "41 Geo.