DECRETALS (Epistolae decretales), the name (see DECREE above), which is given in Canon Law to those letters of the pope which formulate decisions in ecclesiastical law; they are generally given in answer to consultations, but are sometimes due to the initiative of the popes. These furnish, with the canons of the councils, the chief source of the legislation of the church, and form the greater part of the Corpus luris. In this connection they are dealt with in the article on Canon Law.
The author assumes the name of Isidore, evidently the arch bishop of Seville, who was credited with a preponderating part in the compilation of the Hispana (see CANON LAW) ; he takes in addition the surname of Mercator, perhaps because he has made use of two passages of Marius Mercator. Hence the custom of alluding to the author of the collection under the name of the "pseudo-Isidore." The collection is divided into three parts. The first, which is entirely spurious, contains, after the preface and various intro ductory sections, 7o letters attributed to the popes of the first three centuries, up to the council of Nicaea, i.e., up to but not including St. Silvester ; all these are a fabrication of the pseudo Isidore, except two spurious letters of Clement, which were already known. The second part is the collection of councils, classified according to their regions, as it figures in the Hispana; the few spurious pieces which are added, and notably the famous Donation of Constantine (q.v.), were already in existence. In the third part the author continues the series of decretals which he had inter rupted at the council of Nicaea. But as the collection of authentic decretals does not begin till Siricius (385), the pseudo-Isidore first forges 3o letters, which he attributes to the popes from Silvester to Damasus ; after this he includes the authentic decretals, with 35 apocryphal ones, generally given under the name of those popes not represented in the authentic collection, but sometimes also under the names of the others, for example, Damascus, St. Leo, Vigilius and St. Gregory; with one or two exceptions he does not interpolate genuine decretals. The series stops at St. Gregory the Great (d. 604), except for one letter of Gregory II. The forged letters are not, for the most part, entirely composed of fresh material; the author draws his inspiration from the notices on each of the popes given in the Liber Pontificalis; he inserts whole passages from ecclesiastical writers; and he antedates the evidences of a discipline which actually existed ; so it is by no means all invented.
Thus the authentic elements were calculated to serve as a pass port for the forgeries, which were, moreover, skilfully composed ; and the collection thus blended was passed from hand to hand without meeting with any opposition. At most all that was asked was whether those decretals which did not appear in the Liber canonum (the collection of Dionysius Exiguus, accepted in France) had the force of law, but Pope Nicholas having answered that all the pontifical letters had the same authority, they were henceforward accepted, and passed in turn into the later canonical collections. No doubts found expression until the I5th century, when Cardinal Nicholas of Cusa (d. 1464) and Juan Torquemada (d. 1468) freely expressed their suspicions. More than one scholar of the i6th century, George Cassander, Erasmus, and the two editors of the Decretum of Gratian, Dumoulin (d. 1568) and Le Conte (d. 1577), decisively rejected the False Decretals. This contention was again upheld, in the form of a violent polemic against the papacy, by the Centuriators of Magdeburg (Ecclesias tica historia, Basle, ; the attempt at refutation by the Jesuit Torres (Adversus Centur. Magdeburg. libri quinque, Florence, 15 7 2) provoked a violent rejoinder from the Protestant minister David Blondel (Pseudo-Isidorus et Turrianus rapulantes, Geneva, 162o). Since then, the conclusion has been accepted, and all researches have been of an almost exclusively historical character.
BIBLIOGRAPHY.—The best edition is that of P. Hinschius, Decretales Bibliography.—The best edition is that of P. Hinschius, Decretales pseudo-Isidorianae et capitula Angilramni (Leipzig, 1863). In it the authentic texts are printed in two columns, the forgeries across the whole width of the page; an important preface of ccxxviii. pages contains, besides the classification of the mss., a profound study of the sources and other questions bearing on the collection. The nation ality and place of composition has been the subject of much dis cussion. The view that they originated at Rome has long been abandoned. Hinschius and others argue that they were composed in the province of Reims: see for instance Hinschius, Preface, p. ccviii.; Tardif, Histoire des sources du droit canonique (1887) ; Schneider, Die Lehre der Kirchenrechtsquellen (1892) . The latter afterwards inclined to place them in the Province of Tours and at Le Mans, a conclusion defended by Simson, Die Entstehung der pseudoisidorian ischen Falschungen (1886) and by Fournier, "La Question des fausses decretales" in the Nouvelle Revue historique de droit francais et etranger (1887, 1888), and in the Revue d'histoire ecclesiastique de Louvain V. (1906, 1907) .