William Smith, A Dictionary of Greek and Roman Antiquities, John Murray, London, 1875. p 700.

VALERIAE LEGES. In B.C. 508, the consul P. Valerius proposed and carried various leges, the purpose of which was to relieve himself from the suspicion of aiming at kingly power, and to increase his popularity. The chief were a Lex which gave an appeal (provocatio) to the populus against magistratus, and one which declared to be accursed, and devoted the man and his property, who should form a design to seize the kingly power (Liv. ii.8). Owing to these popular measures, the consul received the cognomen of Publicola, by which he is generally known. This statement of the law on Provocatio by Livy is very brief and unsatisfactory. Cicero (de Rep. ii.31) states more distinctly that this Lex was the first that was passed at the Comitia Centuriata, and that the provisions were "ne quis magistratus civem Romanum adversus provocationem necaret neve verberaret." The Lex, therefore, secured the right of appeal to all Roman cives; and it is consistent with this, that some of the Roman cives, the patricians, as Niebuhr states, had already the provocatio to their curiae. This right of provocatio only applied to Rome and a mile round the city, for the Imperium of the consuls beyond this boundary was unlimited (Liv. iii.20, neque enim provocationem esse longius ab urbe mille passuum). Conformably to this, the Judicia quae Imperio continentur comprised among other cases those where the Judicium was beyond the limits of the mille passus. The substance of the two Leges is stated by Dionysius (Antiq. Rom. v.19, 70) with more precision and apparently in accordance with the terms of the Leges. The right of provocatio was intended to protect persons against the summary jurisdiction of the consuls, by giving them an appeal to the dh'moV, and until the plh'qoV decided on their case, no punishment could be inflicted (c70). In c19 it is said that the appeal was also to the dh'moV; and this measure made Publicola popular with the dhmotikoiv, whom we must take to be the Plebs (cf. Dionys. ix.39). Dionysius generally uses dh'moV to signify Plebs; but he also uses plh'qoV in the same sense (vii.65, viii.70, 71, x.40).