Abstract

The origins and nature of the judicial role of the senate in cases which under the republic were the business of the permanent quaestiones have been the subject of long debate, and a satisfactory explanation has yet to be found for the change that had undoubtedly taken place by the reign of Tiberius. The discovery and publication of the senatorial decree which concluded the investigation into the charge brought in A.D. 20 against Cn. Piso following the murder of Germanicus,2 in addition to the wealth of new material it provides for the political history of the period and the understanding of the methods of the historian Tacitus, allows an insight into the relation of the senate to the quaestio maiestatis which may prove useful in unravelling some of the puzzles which have troubled scholars hitherto