Act of Parliament of the United Kingdom

In the United Kingdom, Acts of Parliament are primary legislation passed by the Parliament of the United Kingdom. Acts of the Parliament of the United Kingdom, as a result of the Glorious Revolution and the assertion of parliamentary sovereignty, are supreme law that cannot be overturned by any body other than Parliament.

As a result of devolution, the National Assembly for Wales, the Northern Ireland Assembly, and the Scottish Parliament are able to create primary legislation for their respective devolved institutions. These devolved legislatures are able to create legislation regarding all but reserved and excepted matters. However, Acts of the Parliament of the United Kingdom remain supreme and can overrule the devolved legislatures. By convention, the Parliament of the United Kingdom does not do this without a legislative consent motion.

A draft piece of legislation is called a bill, when this is passed by Parliament it becomes an Act and part of statute law.

Acts of Parliament are classified as either "Public General Acts" or "Local and Personal Acts" (also known as "Private Acts"). Bills are also classified as "public", "private", or "hybrid".

Public General Acts form the largest category of legislation, in principle affecting the public general law applying to everyone across the entire United Kingdom (or at least to one or more of its constituent countries of England, Northern Ireland, Scotland, or Wales). Most Public General Acts proceed through Parliament as a public bill; occasionally, however, a bill is treated as hybrid.

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