Please note that Mommsen uses the AUC chronology (Ab Urbe Condita), i.e. from the founding of the City of Rome. You can use this reference table to have the B.C. dates
From: The History of Rome, by Theodor Mommsen
Translated with the sanction of the author by William Purdie Dickson
The political aim of these enactments--to put an end to the share which the equites had hitherto had in the government--is clear as day; but it as little admits of doubt, that these were not mere measures of a political tendency, but that they formed the first attempt to amend the Roman criminal procedure and criminal law, which had since the struggle between the orders fallen more and more into confusion. From this Sullan legislation dates the distinction-- substantially unknown to the earlier law--between civil and criminal causes, in the sense which we now attach to these expressions; henceforth a criminal cause appears as that which comes before the bench of jurymen under the presidency of the praetor, a civil cause as the procedure, in which the juryman or jurymen do not discharge their duties under praetorian presidency.
The whole body of the Sullan ordinances as to the -quaestiones- may be characterized at once as the first Roman code after the Twelve Tables, and as the first criminal code ever specially issued at all. But in the details also there appears a laudable and liberal spirit. Singular as it may sound regarding the author of the proscriptions, it remains nevertheless true that he abolished the punishment of death for political offences; for, as according to the Roman custom which even Sulla retained unchanged the people only, and not the jury-commission, could sentence to forfeiture of life or to imprisonment,(38) the transference of processes of high treason from the burgesses to a standing commission amounted to the abolition of capital punishment for such offences.
38. Cf. IV. III. Modifications of the Penal Law
On the other hand, the restriction of the pernicious special commissions for particular cases of high treason, of which the Varian commission(39) in the Social war had been a specimen, likewise involved an improvement.
39. Cf. IV. VII. Rejection of the Proposals for an Accomodation
The whole reform was of singular and lasting benefit, and a permanent monument of the practical, moderate, statesmanly spirit, which made its author well worthy, like the old decemvirs, to step forward between the parties as sovereign mediator with his code of law.
Do you see any typos or other mistakes? Please let us know and correct them
Reference address : https://www.ellopos.net/elpenor/rome/4-10-sullan-constitution.asp?pg=47