The Norman kings were often overseas and appointed a Justiciar, Regent or Lieutenant to represent them in the kingdom, as the Sheriff did in the shire. Later this post became known as the Chief Justiciar (or royal capital justiciar), although the titles were not generally used contemporaneously. Some historians claim the first in the post was Roger of Salisbury; Frank Barlow argues in favour of Bishop Ranulf Flambard, a functionary within the household of William I of England, as the first, and points out that the role began, perhaps, with Odo of Bayeux in his relationship with William I.
The Chief Justiciar was invariably a great noble or churchman, and the office became very powerful and important; enough indeed to be a threat to the King. The last great Justiciar, Hubert de Burgh, 1st Earl of Kent, was removed from office in 1231, and the Chancellor soon took the position formerly occupied by the Chief Justiciar as second to the King in dignity, as well as in power and influence. Under King Edward I the office of Justiciar was replaced by separate heads for the three branches into which the King's Court was divided: Justices of the Court of Common Pleas, Justices of the Court of King's Bench and Barons of the Court of Exchequer.
| name | term | King(s) |
|---|---|---|
| Roger of Salisbury | Henry I Stephen | |
| Ralf Basset | 1116 | Henry I |
| Richard Basset | Henry I | |
| Roger of Salisbury | Stephen | |
| Robert de Beaumont, 2nd Earl of Leicester | Henry II | |
| Richard de Luci | Henry II | |
| Ranulf de Glanville | Henry II Richard I | |
| William de Mandeville, 3rd Earl of Essex | Richard I | |
| Hugh de Puiset, Bishop of Durham | Dec. 1189-April 1190 | Richard I |
| William Longchamp, Bishop of Ely | Richard I | |
| Walter de Coutances, Archbishop of Rouen | Richard I | |
| Hubert Walter, Bishop of Salisbury | 1194–98 | Richard I |
| Geoffrey Fitz Peter, 1st Earl of Essex | 11 July 1198 - 14 October 1213 | Richard I John |
| Peter des Roches, Bishop of Winchester | John | |
| Hubert de Burgh, 1st Earl of Kent | John Henry III | |
| Stephen de Segrave | ?-1234 | Henry III |
| Hugh Bigod | 1258 to 1260 | Henry III |
| Hugh le Despencer | 1260-May 1261 | Henry III |
| Philip Basset | May 1261-? | Henry III |
The title of 'Justiciar' was reserved for two or three high officials, the chief one — the Justiciar of Scotia — having his jurisdiction to the north of the River Forth. The Justiciar of Lothian dealt with the part of the kingdom south of the Forth-Clyde line. The role of Justiciar evolved into the current Lord Justice-General, the head of the High Court of Justiciary, head of the judiciary in Scotland and a member of the Royal Household.
The Duke of Argyll still holds the hereditary title of High Justiciar of Argyll, but no responsibilities now attach to it.
In the 12th century, a magister justitiarius appeared in the Norman kingdom of Sicily, presiding over the Royal Court (Magna Curia), empowered, with his assistants, to decide, inter alia, all cases reserved to the Crown. There is no clear evidence that this title and office were borrowed from England; it was probably based on a Norman practice instituted in both realms. In the 13th century the office of justiciar was instituted in several principal localities around Sicily.
In medieval Sweden, the lagman ("lawreader") was the judge, or person learned in law, for a province, an area with several local district courts. Since the position corresponds to the general meaning of 'justiciar', 'justiciar' is often used to translate 'lagman' in English texts. Lagmän were generally also members of the Senate of the realm, an institution corresponding to the English Privy Council. Finally, the Swedish term 'riksdrots' is often translated as 'Lord High Justiciar of Sweden'.
White Wolf's roleplaying game Vampire: The Masquerade adapted the title of Justiciar, but changed the spelling to Justicar. In Vampire: The Masquerade, Justicars are the enforcers of the Traditions of the Camarilla. In a meeting of the Inner Circle every thirteen years, each of the seven clans of the Camarilla each elect a single vampire to serve for the next thirteen years as Justicar for their clan.
Years later, the MMORPG World of Warcraft later picked up the same term, spelling it as Justicar like White Wolf did. Justicar is a PvP title awarded to Alliance players since patch 2.1, which was released on May 22, 2007.