J.P.Sommerville

Although Magna Carta did not settle the conflict between John and his barons, it soon came to be regarded as the fundamental cornerstone of English constitutional law.   Dicitur vulgariter "ut rex vult, lex vadit;" Veritas vult aliter, nam lex stat, rex cadit. (The Song of Lewes, 1264) [Commonly it is said, "as the king wishes, so goes the law;" The truth is quite otherwise, for the law stands, though the king falls."]

In the three centuries following 1215, Magna Carta was repeatedly reissued and reconfirmed. During the seventeenth century, it was used by Parliament to justify their resistance to royal absolutism.

The Founding Fathers of the American constitution also regarded Magna Carta as a landmark on the road to limited government.  "It has been several times truly remarked that bills of rights are, in their origin, stipulations between kings and their subjects, abridgements of prerogative in favor of privilege, reservations of rights not surrendered to the prince. Such was Magna Charta obtained by the barons, sword in hand, from King John." (Alexander Hamilton, The Federalist Papers)

Unlike other statements of natural and constitutional rights such as the Petition of Right (1628) or the American Declaration of Independence (1776), Magna Carta's principles are embedded in a mass of confusing detail.

Key principles

Some of the general principles of Magna Carta are quite clear - in particular, two clauses (39 & 40) on due process of law:

[In practice, there was no single process for all England - it varied in accordance with local custom and the status of the accused; jury trial was only just beginning to replace ordeals. However, the beginnings are evident of the Seventh Amendment right that no person should "be deprived of life, liberty, or property, without due process of law."]

	King John agreed to limit the fines paid on the inheritance of land (reliefs; Clauses 2 & 3) and not to levy scutage (Clauses 12 & 14) without the barons' consent. This marked the origin of limits on arbitrary taxation. The principle of "no taxation without representation" was also to have a long history in Anglo-American constitutionalism.
	Magna Carta's clauses (13 & 41) on the rights of merchants and boroughs acknowledged the importance of trade to the English economy.
	Notions of the "commune of the realm" and the "common counsel of the kingdom" showed that England was already regarded as a political community independent of (and possibly superior to) the king who ruled it.
	Magna Carta did nothing directly for the villeins who made up the mass of England's population. However, it was not simply a treaty of peace between king and barons, like many made on the Continent to settle feudal squabbles. By embedding comprehensive principles in the protection of specific rights, Magna Carta formed the basis for the development of constitutional safeguards of the individual from the government.