The Emergence of Formal Government: The twelfth century saw a shift across northwestern Europe from the predominantly local, informal power arrangements typical of customary law to formal government organized along bureaucratic lines. In England the key reign was that of Henry II (1154-89), when the royal treasury (the Exchequer) and permanent royal courts (the Courts of the Kings Bench and of Common Pleas) became established in Westminster, a suburb of London. Previously the kings court had been itinerant, i.e., it met wherever the king happened to be. The creation of these permanent institutions was part of Henrys thorough re-organization of royal justice, which expanded both geographically throughout the country and socially, across all classes from freemen (see below) up to the highest-ranking noblespreviously the only ones to have regular recourse to the kings court. Serfs, however, were still excluded. Despite this initial exclusion, royal justice gradually undermined the independence of local lords, whose men, both noble vassals and serfs, increasingly escaped lordly control as they sought the right to take their cases directly to the royal courts.
Freemen: In-between lords and serfs were freemen. Though still often recognizing a local lords authority in military and judicial matters, freemen held some of their lands freely and leased other lands from landlords, but in return for rent payments rather than any kind of personal service. Probably not very numerous before ca. 1200 CE, freemen thereafter expanded as a social category, absorbing all of the former serfs by the end of the Middle Ages (ca. 1500 CE). As feudalism and manorialism declined over the later Middle Ages, the class of freemen and freely-held property both gradually became the new normal. These two aspects of freedom, personal and tenurial, developed in tandem with the rise of the state, because both required a central authority capable of guaranteeing ordinary peoples rights, as Magna Carta suggests was already beginning to be the case by 1215.
The Birth of Common Law. The expanded system of royal justice that emerged in the late 1100s and the norms it upheld came to be called the Common Law, which at first meant simply the law that was the same, or common, throughout the country, as opposed to the diversity of regional or local law. Yet this emerging body of national law did not set out to change legal norms themselves; instead the Common Law was conservative in terms of the substantive law, incorporating without radical change many of the customary norms of the law of crime, family, property, and inheritance. The Common Law was very innovative, however, in terms of procedure: it emphasized written documentation (focused above all on royal writs, on which see below), the peaceful resolution of disputes, the use of local juries to establish both law and fact, and a clear hierarchy of courts.
Common Law as Customary or Case Law. The key feature of both English and American versions of Common Law is their heavy reliance on judicial precedent, or case law, as a means of determining what the law is. Because judicial decisions tend both to recognize tradition and to adjust incrementally to evolving social values and popular understandings, Common Law may be understood as a sophisticated type of customary law, notwithstanding its use of written documentation.
Common Law vs Civil Law, etc. As the foundation of the legal traditions of English-speaking countries, Common Law is often contrasted with the Civil Law traditions of continental Europe, which like their Roman law model are based on theoretically comprehensive legal codes, and which (again in theory) leave judges with less discretion in deciding cases. Within Anglophone countries, Common Law in the sense of customary or case law may be contrasted with both statutory law, the law set out by legislative statutes, and, more recently, with regulatory law (the regulations made by executive branch agencies). Historically, this judge-made law (sometimes described pejoratively as legislating from the bench) preceded statutory law in the modern sense by about a century, because Englands first distinct legislative institution emerged only with the establishment of Parliament under Edward I (1272-1307). Despite these contrasts, however, case law also overlaps with statutory and regulatory law, because some laws and regulations merely codify existing practice. Conversely, many statutes or regulations that are at first innovative eventually become incorporated into judicial precedents and customary understandings.
The Grand Jury and the Possessory Assizes
A) The Grand Jury: The Assize of Clarendon, 1166
Henry IIs most important innovation may have been the establishment of the Grand Jury, which created a coherent system for prosecuting crime based on the cooperation of local communities with royal judges (or justices) and the central royal courts. This edict describes its basic operation.
 King Henry, by the counsel of all his barons, for the preservation of peace and the observing of justice, has decreed that an inquest shall be made throughout the separate counties, and throughout the separate hundreds [subdivisions of the county], through twelve of the more lawful men of the hundred, and through four of the more lawful men of each township, who upon oath will speak the truth about: whether in their hundred or in their township there is any man whois publicly reputed as being a robber or murderer or thief; or anyone who harbors robbers or murderers or thieves. And both the [itinerant royal] Justices and the sheriffs shall make inquests in this way. [Then the accused must answer]
 No one in a city or borough or castle or elsewhere shall forbid the sheriffs from coming into their land or soc [area of jurisdiction] to take those who have been charged or publicly reputed as being robbers or murderers or thieves
 And all sheriffs shall cause a register to be kept of all fugitives who shall flee from their counties; and this they shall do before the county assemblies. They shall write down and carry their names to the Justices, so that they may be sought for throughout all England, and their chattels [moveable goods] may be taken for the service of the king.
B) The Writ of Mort dAncestor, Northampton, 1176
The reforms that directly concerned property law (known as the possessory assizes) were based on the use of royal writs, brief written orders from the kingthough actually written by his officialsto initiate lawsuits. A number of stereotyped writs that resemble fill-in-the-blank forms were developed, each of which addressed a common type of legal case. Any freeman could purchase a writ to start a lawsuit against another party, for example to recover property. By this means the royal courts could handle different kinds of legal business for a wide range of litigants. The two key writs excerpted here are often credited with undermining lordly power and helping to create something more like modern property rights. The first, the writ of Mort dAncestor, began a legal action concerning inheritance upon the death of ones predecessor.
 If any freeholder has died, let his heirs remain possessed of such seisin [lawful possession] as their father had in his fee [fief or landed estate] on the day of his death; and let them have his chattels [moveable property] from which they may execute the dead mans will. And afterwards let them seek out his lord and pay him a relief [inheritance tax] and the other things which they ought to pay him from the fee.  And if the heir be under age, let the lord of the fee receive his homage [promise of fidelity or vassalage] and keep him in wardship [guardianship] so long as he ought  And let the widow of the deceased have her dower and that portion of his chattels which belongs to her.
 And if the lord of the fee denies the heirs of the deceased the seisin they claim, the kings justices should call an inquisition to be made by twelve lawful men as to what seisin the deceased held on the day of his death. And according to the result of the inquest let restitution be made to his heirs. And if anyone shall do anything contrary to this and shall be convicted of it, let him remain at the kings mercy.
C) The Writ of Novel Disseisin, 1189
This writ, or royal order, began a legal action to reverse a recent dispossession. It constituted one of the two key methods by which the king rapidly extended his jurisdiction over virtually all property disputes (except those among serfs, who would remain subject to their manorial lords for another century or two). Together with the Grand Jury and the writ of Mort dAncestor, it helped to outlaw virtually all non-royal acts of violence. It thus gave the royal government what Max Weber considered an essential attribute of any effective state: a monopoly over (legitimate) violence. This writ is first described in the first textbook of the new Common Law, known as Glanvill, which was written in about 1189, in ch. 13:
The king to the sheriff, greeting. [name of plaintiff] has complained to me that [name of accused]unjustly and without a judgment has disseised [dispossessed] him of his free tenement [landed estate] in -[name of place]. Therefore I command you that, if the plaintiff gives you security for prosecuting his claim, you are to see that the chattels [moveable property] which were taken from the tenement are restored to it, and that the tenement and the chattels remain in peace until [date]. And meanwhile you are to see that the tenement is viewed by twelve free and lawful men of the neighborhood, and that their names are endorsed on this writ. And summon them to appear before my justices on [date], ready to make their recognition [testimony], together with the accused or his bailiff [representative] if he himself cannot be found.