Constitutions (constitutiones), the generic name for legislative enactments by Roman emperors, took different forms.(a) Like all higher magistrates, emperors had the power to issue *edicts; imperial edicts were used for enactments of a general character (e.g. the *constitutio Antoniniana, extending citizenship to the whole Roman world).(b) The emperor had great judicial powers. His decisions took the form of decrees (decreta). Although the Romans had no theory of binding precedent, such rulings, coming from the emperor, were regarded as authoritative for future cases and were freely quoted by the jurists.(c) The emperor received many petitions and requests for rulings from officials and from individuals. Rescripts (rescripta) were the written answers issued by the imperial chancery. They were of two main kinds. (1) Epistulae (letters) were addressed to officials or public bodies, and were drafted by the department ab epistulis. (2) Subscriptiones (see subscriptions), so called because the emperor validated them by writing at the end ‘scripsi’ or ‘subscripsi’ (‘I have written underneath’), were drafted by the department a libellis in response to petitions (libelli) on a wide variety of subjects from private persons and (rarely) cities (see magister libellorum).