Proceeding in quo warranto

Quo warranto (Medieval Latin for "by what warrant?") is a prerogative writ requiring the person to whom it is directed to show what authority they have for exercising some right or power (or "franchise") they claim to hold.

With the spread of royal justice in the 12th and 13th centuries, private franchises and liberties were increasingly called upon to uphold the king's peace: to act against "malefactors and peace breakers, so that it may appear that you are a lover of our peace". From 1218 onwards, royal Eyres also began using the old writ of quo warranto – a court order to show proof of authority, as for example (literally) "By what warrant are you the sheriff?" – to investigate the origins of such franchises. An inquest of 1255 began examining such liberties nationwide; and the same enquiry was taken up again by King Edward I of England in 1278, when he decreed in the Statute of Gloucester that "We must find out what is ours, and due to us, and others what is theirs, and due to them".

From one point of view this can be seen as an attempt to investigate and recover royal lands, rights, and franchises in England, in particular those lost during the reign of his father, King Henry III of England. From another, it was less of an attack on franchises as a clarification of them: in Hilda Johnstone's words, "Edward's aim, it is clear, was from the first not abolition but definition".

A similar ambiguity surrounds the role of the justices that, from 1278 to 1294, Edward dispatched throughout the Kingdom of England to inquire "by what warrant" English lords claimed their liberties and exercised jurisdiction, including the right to hold a court and collect its profits. Some of the justices demanded written proof in the form of charters, others accepted a plea of "Immemorial tenure"; and resistance and the unrecorded nature of many grants meant that eventually, by the Statute of Quo Warranto (1290), the principle was generally accepted that those rights peacefully exercised since 1189 – the beginning of the reign of Richard I, which is the legal definition in England of the phrase "time immemorial" – were legitimate.

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