The dataset has been created from printed lists of prisoners tried at Middlesex or Westminster Sessions of the Peace. The information given includes the name of the prisoner, age, occupation, level of literacy, previous convictions, offence charged with, date tried, verdict and sentence. The Calendars represent a source for offences and punishments at a lower level in the justice system than the Old Bailey, in order to trace previous offending and recidivism. The prisoners in the Calendars can be linked to Old Bailey offenders directly using information about previous offending, and more probabilistically by linkage on personal information (names, ages, occupations, etc).