These were the famous Ordinamenti della Giustizia of 1293, by which all who were not of the arti were definitely excluded from the signory.
Judgment in matters concerning the Ordinamenti was delivered in a summary fashion without appeal.
The leading spirit of this reform was Giano della Bella, a noble who by engaging in trade had become a popolano; the grandi now tried to make him unpopular with the popolani grassi, hoping that without him the Ordinamenti would not be executed, and opened negotiations with Pope Boniface VIII.
In 12 9 5 a signory favourable to the grandi enacted a law attenuating the Ordinamenti, but now the grandi split into two factions, one headed by the Donati, which hoped to The abolish the Ordinamenti, and the other by the Cerchi, which had given up all hope of their abolition; after wards these parties came to be called Neri (Blacks) and Bianchi (Whites).
The priori were reduced to 8 (2 popolani grassi, 3 mediani and 3 artifici minuti), while the gonfaloniere was to be chosen in turn from each of those classes; the grandi were excluded from the administration, but they were still admitted to the consiglio del comune, the cinque di mercanzia, and other offices pertaining to the commune; the Ordinamenti were maintained but in a somewhat attenuated form, and certain grandi as a favour were declared to be of the popolo.
The ordinamenti della giustizia of that year robbed the nobility of all political power.