A repeal is the removal or reversal of a law. This is generally done when a law is no longer effective, or it is shown that a law is having far more negative consequences than were originally envisioned.

Major repeals in history include:

• The repeal of the Act of Union 1800, providing for the union between Great Britain and Ireland as the United Kingdom. The union was partially repealed in 1922, when under the Anglo-Irish Treaty of 1921, twenty-six of the thirty-two Irish Counties became the Irish Free State and ceased to be part of the United Kingdom.
• The Corn Laws in England, repealed in 1846 after a passionate campaign.
• Repeal of Prohibition in the United States. Enacted by the Eighteenth Amendment to the United States Constitution, it proved to be so ineffective that it had to be repealed by the Twenty-first Amendment. This is the only constitutional amendment to be repealed in the U.S., and also the only time the Constitution was used to set social policy.
• The repeal of the acts that caused taxes during the colonial times of the US.
• The Poor Laws in England in 1948.
• The massive Statutory Law Revision Act of 2007 in the Republic of Ireland, through which 3,225 Acts were repealed, dating back over eight centuries to 1171 and the earliest laws enacted by England when it began its invasion of Ireland. The statutes repealed include a number of Acts of significant historical interest, including an Act of 1542 providing that the Kings of England shall be Kings of Ireland. This Act is the largest single repealing statute in the history of Ireland.

If a campaign for the repeal of a particular law gains particular moment, an advocate of the repeal might become known as a "repealer". This happened in 19th century Britain to a group in favour of the re-separation of Ireland from the United Kingdom

Many repeals are the result of changes in society, such as the old Jim Crow laws or blue laws. Other repeals are for more mundane things, such as century-old laws against dancing or cabarets. Some repeals are of extremely old and outdated laws that now seem bizarre, such as one from the 19th century against bathing.

The motion to rescind, repeal, or annul is used in parliamentary procedure to cancel or countermand an action or order previously adopted by the assembly.

See also

• Abrogation
• Derogation
• Desuetude
• Recall election
• U.S. laws that have been repealed

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