This article presents new source material relating to the prosecution of the Hampshire and Wiltshire ‘Swing’ rioters at the special commissions convened at Winchester and Salisbury in December 1830 and January 1831. This material comes from the diary of Godfrey Tallents (1812–77), the eldest son of the attorney and political agent William Edward Tallents (1780–1837), who assisted in the prosecution of the rioters. Godfrey Tallents accompanied his father to Winchester and acted as his junior. The relevant diary entries, which are reproduced in their entirety, offer important first-hand testimony from a participant in the special commission. They offer a new and welcome perspective on events, broadening the base of archival material upon which historians of the subject (such as the Hammonds and Rudé and Hobsbawm) have traditionally relied.