The consuls were supreme criminal judges at the beginning of the republic, and were clothed with unlimited power in matters of life and death. This is shown by the condemnation and execution of the sons of Brutus and their fellow-conspirators.[18] Associated with the consuls were, at first, two annually appointed quæstors whom they nominated. The functions of the quæstors were as unlimited as those of their superiors, the consuls; but their jurisdiction was confined chiefly to criminal matters and finance. The tribunes, sacred and inviolable in their persons as representatives of the _plebs_ and as their protectors against patrician oppression, exercised at first merely a negative control over the regular magistracies of the community. But, finally, they became the chief public prosecutors of political criminals. The prætors, whose chief jurisdiction was in civil matters, were potentially as fully criminal judges as the consuls, and there may have been a time when a portion of criminal jurisdiction was actually in their hands. In the later republic, they presided over the _quæstiones perpetuæ_, permanent criminal tribunals. The ædiles are found in Roman history exercising functions of criminal jurisdiction, although their general powers were confined to the special duties of caring for the games, the market, and the archives. But the criminal jurisdiction of the magistrates who replaced the king at the downfall of the monarchy was abridged and almost destroyed by the famous _lex Valeria_ (_de provocatione_). This law was proposed 509 B.C. by Publius Valerius, one of the first consuls of Rome, and provided that no magistrate should have power to execute a sentence of death against a Roman citizen who had appealed to the judgment of the people in their public assembly. This _lex_ was the _magna charta_ of the Romans and was justly regarded by them as the great palladium of their civil liberty. And it was this law that inaugurated the popular jurisdiction of the _comitia_. The result was that for more than three hundred years the final determination of the question of life or death was in the hands of the people themselves. From the passage of the Valerian law the function of the magistrates was limited to the duty of convincing the people of the guilt of an alleged criminal against whom they themselves had already pronounced a preliminary sentence. The magistrates were, therefore, not so much judges as prosecutors; the people were the final judges in the case.