Adoption and amendment

The idea of endowing a country with a single written constitution is relatively modern, though now widespread, so that the UK is one of the rare exceptions. Furthermore in a large number of countries the constitution follows some decisive event in national history: war, revolution, independence, federation and the like. This ensures that methods of adoption vary widely. The oldest and most prestigious - that of the USA - was adopted by agreement among the 13 states followed by ratification by elected conventions within them; its Bill of Rights (technically, if confusingly, called Amendments) was ratified by the State legislatures. By a seemingly similar method, but in the very different circumstances of the defeat of Nazi Germany, the constitution of the Federal Republic of Germany, finally approved by a Parliamentary Council and called the 'Basic Law', entered into force when notice of its ratification by representative assemblies in over two-thirds of the Laender was published: on 23 May 1949. By contrast, one of the most recent documents - that of the Russian Federation - bypassed the legislature (which the President had dissolved) and was voted directly by the people on 12 December 1993. According to the official returns, 54.8% of the electorate voted, of whom 58.4% were in favor. In between these two methods are many other techniques such as that of the 1958 French constitution which involved both approval by the legislature under procedure laid down by the existing constitution and then by the people in a referendum.

Both legal and political importance attach to the methods by which a constitution may be amended. They may divide the amending power among people, legislature, and executive, or between a federation and its components. They may express basic values by declaring certain features to be unamendable: the republican form of government in France and Italy, and in Germany the basic human rights and the federal structure. Some constitutions specify that matters like this may be amended only by referendum or by an entirely new constitution (e.g. the new Russian document). In federal systems, amendments normally require special majorities in the federal legislature followed by ratification by a special majority of the states. This is the US provision, now adopted for some types of amendment by the Russian Federation.

A common method is to require a special majority in the legislature - two-thirds in Germany, three-fifths in France, with similar systems in India and other Commonwealth countries (and this used to be the pattern in the Soviet bloc). Another parliamentary alternative is to require a second vote (Italy, Denmark, Finland). Finally, some systems divide the amending power between legislature and people, by requiring a referendum either for certain types or methods of amendment (Denmark, France, Ireland) or for any (e.g.Japan).

Unlike the systems just described, the UK constitution is indeterminate, indistinct and unentrenched. It is found in no single constitutional document. The volumes entitled 'Constitutional Law' in the official edition of the 'Statutes in Force' print 138 Acts of Parliament, while a quite separate volume on 'Rights of the Subject' gives another thirty-two, including what is left of Magna Carta 1215. Furthermore many matters in written constitutions, such as the procedure on a finance bill or a vote of no confidence, are governed entirely by custom, convention and Standing Orders of the Houses of Parliament. The basic constitutional instruments are presumably those of 1707: the Treaty of Union and Acts of Union of the English and Scottish Parliaments. From 1800 Ireland was also part of the UK until the Ireland Act 1949 finally admitted that it was no longer part of His Majesty's dominions. Since 1922 the UK has in effect consisted of Great Britain and Northern Ireland.

The British constitution is indistinct in that there is no way to tell whether 'ordinary' laws are in conflict with those forming part of the constitution (although since 2 October 2000 the courts may declare that a particular statute (though still valid) is incompatible with the Human Rights Act 1998. The constitution is unentrenched in that any element may be changed by an Act of Parliament passed in exactly the same way as any other piece of legislation.