This book approaches the subject of late Roman law from the perspective of legal practice revealed in courtroom processes, as well as more 'informal' types of dispute settlement. From at least the early fourth century, leading bishops, ecclesiastics, and Christian polemicists participated in a vibrant culture of forensic argument, with far-reaching effects on theological debate, the development of ecclesiastical authority, and the elaboration of early 'Canon law'. One of the most innovative aspects of late Roman law was the creation and application of new legal categories used in the prosecution of 'heretics'. Leading Christian polemicists not only used techniques of argument learnt in the late Roman rhetorical schools to help position the Church within the structure of Empire, they also used those techniques in cases involving accusations against 'heretics'- thus defining and developing the concept of Christian orthodoxy itself.