Assize Courts
From the 12th century until the passing of the Courts Act of 1971 serious crimes were usually brought before pairs of professional judges who travelled through groups of counties on circuits, holding what was known as 'assize' sessions in each county on a biannual basis. The Soke of Peterborough was included within Northamptonshire which was part of the Midland circuit (except 1864-1875 when it was transferred to the Norfolk Circuit). The Assize Court would often get serious or complex cases referred up to it from the Quarter Sessions Court. However, their jurisdiction often coincided as the Assize Courts would refer cases back to the Quarter Sessions when the matter had not been dealt with before the assize judges moved on.
Clerks of Assize kept all the records for the circuits. These are held at the National Archives. Material relating to the Midlands is held in ASSI 12 and ASSI 80.