Four main courts
Of the four main courts, the Common Pleas, King's Bench, and Chancery sat in the Hall itself, and the Exchequer in an adjoining building.
Until the reign of Henry II (1154-89), royal justice was administered wherever the King happened to be, but under Henry, a royal ordinance decreed that five judges should sit in a certain place rather than travel with the King for the convenience of litigants.
Thus by 1178, there were judges sitting in the Hall during the King's absence.
After the Magna Carta
In 1215, the Magna Carta stipulated that common pleas should be held in a fixed place: this was usually Westminster Hall.
As the treaty also created two separate jurisdictions, two separate courts known Common Pleas and King's Bench were formed during the 13th century - the former for civil litigation and the latter for cases of interest to the King (effectively the supreme court for criminal cases).
The King's Bench used the southern end of the Hall, with the King sitting in the marble chair when he presided, while Commons Pleas was located near the chief door of the Hall on the north.
Development of courts
The Chancery gradually became a distinct court in the 15th century, where the Lord Chancellor provided redress for those unable to obtain it under the strict rules of common law. By the late 15th or early 16th century, the King's Bench and Chancery were established in opposite corners at the south end of the hall.
The accommodation provided for these courts was fairly simple, and had to be dismantled easily for feasts and other events. Inventories from 1320 indicate that the judges sat on raised benches which were 8 metres (27 feet) long, with their senior clerks on similar benches at their feet.
Bars of oak planks defined each court, within which were benches for the litigants.