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
The supreme magistrates of the state were at this period practically
the three colleges of the tribunes of the people, the consuls and
praetors, and the censors. They all emerged from the Sullan
restoration with materially diminished rights, more especially
the tribunician office, which appeared to the regent an instrument
indispensable doubtless for senatorial government, but yet--
as generated by revolution and having a constant tendency to
generate fresh revolutions in its turn--requiring to be rigorously
and permanently shackled.
The tribunician authority had arisen out
of the right to annul the official acts of the magistrates by veto,
and, eventually, to fine any one who should oppose that right and to
take steps for his farther punishment; this was still left to the
tribunes, excepting that a heavy fine, destroying as a rule a man's
civil existence, was imposed on the abuse of the right of intercession.
