Brevia files are the main series of writ files of the court, containing writs returned by the sheriff of each county. The surviving records consist of whole intact files, partial files and loose writs. Each file relates to a set 'return day' within one of the four annual law terms (Michaelmas, Hilary, Easter and Trinity); writs ordered to be returned by that day were filed together when they came into the court.
Each writ is endorsed with the sheriff's account of what he had done in response to it, and the returns which he had been asked to send in are sewn to the writs. These consist mainly of jury panels, lists of pledges, records of pleas in inferior courts, and occasional inquisitions. The records of inferior courts had usually been taken on writs of recordare facias loquelam, and came especially from the courts of counties, but also those of hundreds and wapentakes and occasionally of manorial courts.
From 1 May 1292 the judicial writs issued by the court are 'signed' by the clerks who wrote them. From the early 1290s some writs are annotated with the number of the plea roll rotulus on which the order to issue it had been recorded; by 1300 this is the norm.
In earlier centuries the brevia files include letters to the justices, mainly dedimus potestatem writs, and exigents orders. From that late sixteenth century onwards, the dedimus potestatem writs are in the concords of fines files in C 24/1- C 24/13 and the exigents orders are with other unsorted outlawry writs in CP 59.
The records are in Latin, except between Trinity 1651 and Trinity 1660 and from Easter 1734 onwards when they are in English.