(1) The Emperor was able to influence the election of magistrates in the popular assembly, and (2) he could assume the powers of censor, and perform alectio senatus. Augustus purified the senate on several occasions. The censor, or he who possessed the censorial power, under the Principate—always (after 22 B.C.), though not necessarily, the Princeps himself with, or without a colleague—could not only place by adlectio a non-senator in the senate; but could assign him a place in a rank higher than the lowest. In fact, adlection among the quaestorians (the lowest class) was uncommon; adlection either into the tribunician or into the praetorian class was the rule. Adletion into, the highest rank of all, the consulates, was practiced by Caesar the Dictator, but not by Caesar the first Princeps or any of his successors up to the third century. When it became usual, as it did before the death of Augustus, to elect half-yearly instead of annual consuls, the influence which the Emperor could exert at the elections, gave him much of the power which Caesar the Dictator exerted by adlectio inter consulares. A list of the senate was made up every year.
The Emperor also exerted a great influence on the constitution of the senate in another way. Admission to the senate in the ordinary course depended on the quaestorship; and the quaestorship depended on the vigintivirate. The rule was that only those who belonged to the senatorial rank could be candidates for thevigintivirate. Here adlection could not come in; but the Emperor assumed the right of admitting as candidates for the vigintivirate persons outside the senatorial class, by bestowing upon them the latus clavus. Thus a young knight, not born of a senatorial family, might, by the Emperor's favor, enter on a senatorial career and become a member of the senate. The poet Ovid, who by birth belonged to the equestrian order, is a well-known example. The Emperor seems to have also had the power of granting a dispensation which allowed persons who had not been vigintiviri to become quaestors. It should be observed that in the senatorial career (cursus honorum) military service (generally for a year in one legion) was necessary. The usual steps were (1) vigintivirate, (2) military tribunate, (3) quaestorship, (4) aedileship or tribunate, (5) praetorship, (6) consulate. Hence the vigintiviral offices are called by Ovid “the first offices of tender age”.
The Princeps was himself not only a senator, but the "Prince of the senate"; his name stood first on the list of senators, and he possessed the right of voting first. He did not, however, adopt princeps senatus as one of his titles, as it was his policy rather to distinguish himself from than to identify himself with the senate.Special clauses of the lex de imperio conferred upon him further rights in regard to the transactions of that body. He had the rights of summoning the senate—a right which he might have claimed by virtue of the tribunician power itself,—and of introducing bills (relatio) either orally or, in case of his absence, by writing, the proposal being couched in the form of an oratio (or litterae) A.D.. senatum.His tribunician power gave him the right, as we have already seen, of cancellingsenates consulta. The reports of the transactions in the curia were always laid before Augustus when he was not present himself, and he appointed a special officer, as his representative, to see that the reports were drawn up in full and nothing important omitted. This officer was curator actorum (or ab actis) Senatus.
Augustus introduced the practice of forming senatorial committees to consult beforehand, in conjunction with himself, on measures which were to come before the senate. They consisted of one magistrate from each college and fifteen senators chosen by lot every six months, and formed a sort of "cabinet council". In the last year of his life, when, owing to his weakness and advanced age, he could no longer appear in the curia, a small senate was empowered to meet in his house and pass resolutions in the name of the whole senate. This body consisted of his son, his two grandsons, the consuls in office and the consuls designate, twenty senators chosen for a year, and other senators whom the Emperor himself selected for each sitting. This political consilium was no part of the constitution, and was in fact, under the early Principate, only adopted by Augustus himself and his successor Tiberius. It must be carefully distinguished from the judicial consilium, which will be mentioned below.
It has been already mentioned that the joint rule of the Empire by the Emperor and the senate is sometimes called a dyarchy. It was a dyarchy that might at any moment become openly, as it was virtually, a monarchy. For the Emperor possessed the actual power through his control of the army, and if he had chosen to exert force he might have destroyed the political existence of the senate. But the change of the dyarchy into a monarchy was wrought gradually, and was partly due to the incompetence of the senate, which invited the interference of the sovereigns. The maius imperium was changed by degrees into the direct rule of those provinces which were not part of the Emperor's proconsular province. But Augustus was thoroughly in earnest in giving to the senate a distinct political position and substantial powers. He carefully abstained from interfering in the provinces which were not within his Imperium. He was a man of compromise, and the constitution which he framed was intended to be a compromise between the democratic monarchy, which as the son of Julius he really represented, and the aristocracy. He was anxious to wipe out the memory of the civil wars and to have it forgotten that he had been the champion of the democracy. While he continued to bear the name of the divine Julius, he seems not to have cared to dwell on the acts of the great Dictator; and it has often been noticed how rarely the poets of the Augustan age celebrate the praises of Julius Caesar. We may safely say that no statesman has ever surpassed Augustus in the art of withholding from political facts their right names.
There are many points in the Augustan system which are not plain in their constitutional bearings. But the general lines are clear enough. The careful balancing between the rights and duties of the two political powers produced some artificial arrangements which could not last, and which were soon altered, either formally or tacitly, at the expense of the senate. But the main principle of the system founded by Augustus—the fiction of the independent and co-ordinate government of the senate—was not entirely abandoned for three centuries.
The division of the labors and privileges of government between the senate and the Emperor may be considered under five heads: administration, jurisdiction, election of magistrates, legislation, and finances.
(1) Most of the administrative functions, which the senate discharged under the Republic, especially in its later period, did not belong to that body by constitutional right, but were acquired at the expense of the supreme magistrates, to whom they truly belonged. Many of these powers were confirmed to it under the Empire.
a. The powers which the senate had exercised in the sphere of religion, such as the suppression of foreign or profane rites, it continued to exercise in the imperial period.
b. The rights of making war and peace, and negotiating with foreign powers, were taken away from the senate; but in unimportant cases the Emperor sometimes referred foreign embassies to that body.
c. The authority of the senate in the affairs of Italy continued unimpaired.
d. The affairs of Rome were at first entirely under the management of the senate, but the incompetent administration of that body soon demanded the intervention of the Emperor
e. The provinces were divided into imperial and senatorial; and the administration of the latter was in the hands of the senate. But the Emperor had certain powers in the senatorial provinces, as will be explained in a later chapter. On the other hand, the senate had a small hold on the imperial provinces (except Egypt), in so far as the Emperor appointed only senators as his governors.
(2) The senate, as the council of the chief magistrates, sometimes exercised judicial functions under the Republic, as for example in the case of the Bacchic orgies (186 B.C.). But such cases were only exceptional. Augustus made the senate a permanent court of justice, in which the consul acted as the presiding judge. This court could try all criminal cases; but in practice