As regards the sources of law, even the utterances of the People were for some time elicited. Leges and Plebiscita—specimens of which are to be found in the Leges Juliae of Augustus, the Lex Aelia Sentia belonging to the reign of the same monarch, the Lex Junia Norbana of the reign of Tiberius, the Leges Claudiae of the Emperor Claudius — continued to be passed during the early Principate. The last trace of legislation belongs to the reign of Nerva (96-98 a. d.) Ref. 137.
Even before legislative power had been surrendered by the Comitia, it had begun to pass to the Senate; and down to the third century a.d., such general ordinances as tended to alter the fundamental legal relations of Roman citizens to one another were generally expressed in the form of Senatusconsulta. The Senatusconsultum was a true source of the Jus Civile. Yet it did not attain the formal structure, or always adopt the imperative utterance, of a law. Its utterances are often couched in an advisory form Ref. 138, as though the Senate of this period, like that of the Republic, were merely giving counsel to a magistrate. Gaius attributes to these decrees ‘the binding force of law’; and it does not seem that the early doubts as to whether the Senate could pass ordinances immediately binding on the community Ref. 139 survived the beginning of the Principate.
The Praetor’s edict still continued to be issued; nor are we told that the edictal power was in any way infringed during the early Principate. But there are two considerations which would lead us to conclude that it was seriously weakened. The first is based on the fact that edictal power in the highest degree was conferred by law on the Princeps himself Ref. 140; and the existence of two interpreters of the civil law possessing equal authority is almost inconceivable. The second consideration rests on the probability that the Praetor’s rulings in detail were subject to the veto of the Princeps. A new ruling was often the basis for a new formula and a new edict, and if the first of these was inhibited, its successive developments could not be realized. Progressive legislation was effected elsewhere, in decrees of the Senate and in the imperial constitutions; and the final sign that the creative work of the Praetors was a thing of the past was given when, in the reign of Hadrian (117-138 a.d.), and therefore probably in the lifetime of Gaius, the work which Ofilius had begun Ref. 141 was perfected by the jurist Salvius Julianus. He reduced the edict to a fixed and definite system Ref. 142; and from this time onward the Edictum Perpetuum was, in its essential features, unalterable. Absolute validity was given to the new redaction by a Senatusconsultum introduced by a speech from the Emperor Hadrian, who declared that any new point, not contemplated in the edict, should be decided by analogy with it Ref. 143. It is probable that such new points were still mentioned in successive edicts; for it is certain that the edict still continued to be issued annually. The work of Julian could, therefore, never have been meant to be unalterable in a literal sense. Such invariability would indeed have been impossible; for, though changes in law were now beginning to be made chiefly by ordinances of the emperor, yet these very changes would necessitate corresponding changes in the details of the edict. The fixity of Julian’s edict was to be found both in its structure and in its leading principles; in the order in which the rules of law were marshalled and in the general significance of these rules. It has been supposed that Julian’s work was not confined to the edict of the Praetor Urbanus, but that he dealt also with the edicts of the Praetor Peregrinus and of the Curule Aediles Ref. 144. He may have treated these edicts separately; but the three may have been combined in a single comprehensive work which was spoken of as ‘The Edict Ref. 145.’
By the side of these sources of law which survived from the Republic stood the new authority, the Princeps. He was not regarded as, in the strict sense, a legislative authority; but he or his advisers exercised a profound influence on the growth and structure of law in virtue of his power of issuing Edicts, Decrees, Rescripts, and Mandates. The Edictum of the Princeps was, like that of the Praetor in the Republic, technically an interpretation of law, but, like the Praetor, the Princeps could supplement and alter under the guise of interpretation: and his creative power, as exercised by his edictal authority, was very great. An edict of an emperor did not necessarily bind his successors; but, if it had been accepted as valid by a series of emperors, it was considered to be a part of the law, and its subsequent abandonment had apparently to be specified by some definite act of repudiation Ref. 146. The Decretum was a judgment of the Princeps as a court of justice; and, unless it was rescinded in a succeeding reign, its validity as a precedent seems to have been unquestioned. The Rescriptum was technically an answer to a letter by which the advice of the Princeps was sought; but the word soon came to be used for the Princeps’ letter (Epistola) itself. It contained instructions either on administrative or on judicial matters. In its first capacity, it was addressed to some public official subordinate to the emperor; in its second, it was addressed either to the judge or to the litigant. It was elicited either as an answer to the consultation (Consultatio) of an official or a judge who hesitated as to his course of procedure, or as a reply to a petition (Libellus, Supplicatio) of one of the parties to a suit. The Rescript which dealt with judicial matters might settle a doubtful point of law by showing, or extending, the application of an existing principle to a new case. The Rescript was the most powerful instrument of law-making wielded by the Princeps. The definiteness of its form gave the opinion an authority which, once accepted by a successor, could not easily be questioned; while the immense area over which these letters of advice were sent kept the Princeps in touch with the whole provincial world, and caused him to be regarded by the provincials as the greatest and most authentic interpreter of law. The Edicts, Decrees, and Rescripts came to be described by the collective name of ‘Imperial Constitutions’ (Constitutiones Principum), and by the time of Gaius they were held to possess, in a uniform degree, ‘the binding force of law Ref. 147.’ On a lower level, with respect to legal validity, stood the Mandatum. This was a general instruction given to subordinate officials, for the most part to governors of provinces, and dealt usually with administrative matters, although sometimes it had reference to a point of law. Such mandates might be, and often were, withdrawn by the Princeps who had issued them, or by his successor. Hence it was impossible to attach perpetual validity to their terms. But, when a mandate dealt with a precise point of law, and was renewed by successive emperors, it must have acquired the force of a Rescript Ref. 148.
§ 17.: Changes in Procedure under the Principate.
The creation of the office of Princeps, and the extension of the authority of the Senate, exercised an influence on jurisdiction as well as on legislation. The two new features of the judicial system were the growth of extraordinary jurisdiction and the growth of Courts of Appeal. The name ‘extraordinary’ (extra ordinem) was given to all jurisdiction other than that of the ordinary civil and criminal courts (Judicia Ordinaria) which had survived the Republic. It often dealt with cases not fully provided for by these courts; and its chief characteristic was that the cognizance (Cognitio), both on the question of law and on the question of fact, was undertaken solely by the magistrate or by a delegate nominated by him (judex extra ordinem datus) Ref. 149. In civil matters, the Princeps sat as such an extraordinary court, and either exercised, or delegated, jurisdiction in matters such as Trust or Guardianship. He might take other cases, if he willed; but his jurisdiction was always voluntary; and, if he declined to act, the case went before the Praetor. In criminal matters, two high courts of voluntary and extraordinary jurisdiction were created—that of the Princeps and that of the Senate. The Princeps might take any case, but often limited his intervention to crimes committed by imperial servants or by officers of the army. The jurisdiction of the Senate was especially concerned with offences committed by members of the upper ranks of society, or with crimes of a definitely political character.
The system of appeal introduced by the Principate was of a complicated character, and many of its features are imperfectly understood. It seems that, at Rome, the Princeps could in civil matters veto, and perhaps alter, the decision of