The average written constitution lasts about 19 years, close to Jefferson's guess
Thomas Jefferson thought a constitution should expire after roughly 20 years, since the earth belongs to the living. Modern studies find that newly written national constitutions survive about 19 years on average. Many collapse within a decade, and about one in ten does not make it past its first year.
A constitution is the set of fundamental principles or precedents that make up the legal basis of an entity and govern how it runs. Collected in one document it is codified; the United Kingdom's, by contrast, is spread across statutes, court rulings and treaties. Constitutions exist at many levels, from nations to companies and clubs, and the treaty founding an international organisation serves as its constitution.
The size range is startling. India's is the longest written national constitution, at 146,385 words in English, and Monaco's the shortest at 3,814. San Marino may have the oldest active written constitution, with core documents in force since 1600, while the US Constitution is the oldest codified one still operating. Since 1789 nearly 800 constitutions have been adopted by independent states. Frequent turnover often stems from political impatience and rushed drafting; a 2009 study put average drafting time at about 16 months, though Myanmar's 2008 text took over 17 years in secret.
The word comes via French from the Latin constitutio, used for imperial orders and later for weighty papal decrees, still called apostolic constitutions. William Blackstone used the word differently, for breaches of public trust serious enough to justify revolution, and explicitly rejected anything like judicial review. Modern constitutions grant powers on condition that limits are obeyed. Acts within authority are intra vires; those outside it are ultra vires, void from the outset if a court so finds.
Legitimacy is debated. Some ground it in the consent of the governed, others in reason, and Hegel saw a constitution as the slow work of centuries in a nation's consciousness. Critics warn of the dead hand problem, in which long-gone generations bind the living through texts that are hard to amend. The deepest roots may lie in Sumer: the Lagash king Urukagina issued a justice code around 2300 BC that eased taxes on widows and orphans.
Source: Constitution
