Magistratum gerens, audi et iuste et iniuste.

Being in office, it is your duty to hear all that can be said on the business before you by either party, before you decide on its merit.

«Qui statuit aliquid, parte inaudita altera,
Æquum licet statuerit, haud æquus est».

He who determines a cause without hearing both the parties, though he passes a just sentence, acts unjustly.