Constitution and constitutionalism
The constitution of a state is the collection of rules and principles according to which the state is governed. In antiquity the most important function of a constitution was to determine who should rule. The criterion which served as the basis for assigning political power reflected the ethos of the society. Thus each constitutional form exercised a moulding influence on virtue; the good citizen was a different being in an oligarchy, a democracy and an aristocracy (Aristotle). Although modern constitutions are far more complex, still the rules they establish for acquiring and exercising governmental power will usually embody the underlying norms and ideology of the polity.
The constitution of the modern nation state contains three main elements. First, it establishes the principal institutions of government and the relationships among these institutions. These institutions may be structured on traditional western lines of a division of executive, legislative and judicial responsibilities. The constitutions of one-party states gives greater emphasis to the structures of the governing party, while those based on theocratic principles assign a dominant position to religious offices and institutions. Second, constitutions provide for a distribution of governmental power over the nation's territory. In a unitary state, local units of government are established as agencies of the central government. The constitution of a federal state assigns power directly to central and local levels of government. Third, constitutions provide a compendium of fundamental rights and duties of citizens including their rights to participate in the institutions of government. Some constitutions emphasize economic and social rights as much, if not more, than political and legal/procedural rights.
In most countries there is a single document called 'The Constitution' which contains most of the significant elements of the constitutional system. But this is not the only form in which the rules of a constitution may be expressed. They may also take the form of ordinary laws such as statutes or decrees, judicial decisions or well-established customs and conventions. The United Kingdom is distinctive in that it does not have a document known as the Constitution; all of its constitutional rules are expressed more informally as statutes, judicial opinions, customs and conventions. Since the American Revolution the worldwide trend has been very much towards the codification of constitutional norms. New states established in the aftermath of revolution, the withdrawal of empire and world war have relied on a formal constitutional text to set out their basic governmental arrangements. However, even in these new nations, statutes, judicial decisions and conventions usually supplement the formal constitution.
A country may have a constitution but may not enjoy constitutionalism. Constitutionalism is a political condition in which the constitution functions as an effective and significant limit on government. Where constitutionalism characterizes a regime, the constitution is antecedent to government, and those who govern are constrained by its terms. The constitutional rules of such a regime are not easily changedeven when they are obstacles to policies supported by leading politicians. Thus, constitutional government is said to be 'limited government' (Sartori, 1956). The limits imposed by a constitution are sometimes said to embody a 'higher law'the enduring will of a peoplewhich constitutes the basis of a legitimate check on the will of governments representing transient majorities (Corwin, 1955; McIlwain, 1947).