Amendments

A constitutional amendment refers to the modification of the constitution of a nation or state. In many jurisdictions the text of the constitution itself is altered; in others the text is not changed, but the amendments change its effect. The method of modification is typically written into the constitution itself.

Most constitutions require that amendments cannot be enacted unless they have passed a special procedure that is more stringent than that required of ordinary legislation. Examples of such special procedures include supermajorities in the legislature, or direct approval by the electorate in a referendum, or even a combination of two or more different special procedures. A referendum to amend the constitution may also be triggered in some jurisdictions by popular initiative.

Australia and Ireland provide examples of constitutions requiring that all amendments are first passed by the legislature before being submitted to the people; in the case of Ireland, a simple majority of those voting at the electorate is all that is required, whereas a more complex set of criteria must be met in Australia (a majority of voters in a majority of states is also necessary). Switzerland has procedure similar to that of Australia.

The special procedures for the amendment of some constitutions have proven to be so exacting that of proposed amendments either few (8 Amendments out of 44 proposed), as in Australia, or none, as in Japan, have been passed over a period of several decades. In contrast, the constitution of the U.S. state of Alabama has been amended over 800 times since 1901.

There are a number of formal differences, from one jurisdiction to another, in the manner in which constitutional amendments are both originally drafted and written down once they become law. In some jurisdictions, such as Ireland, Estonia, and Australia, constitutional amendments originate as bills and become laws in the form of acts of parliament. This may be the case notwithstanding the fact that a special procedure is required to bring an amendment into force. Thus, for example, in Ireland and Australia although amendments are drafted in the form of Acts of Parliament they cannot become law until they have been approved in a referendum. By contrast, in the United States a proposed amendment originates as a special joint resolution of Congress that does not require the President to sign and that the President can not veto.

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