Deuteronomy 25:1

If there be a controversy between men
Between two or more:

and they come unto judgment;
into a court of judicature, bring their cause thither:

that [the judges] may judge them;
who were never less than three; the great sanhedrim at Jerusalem consisted of seventy one, the lesser court was of twenty three, and the least of all three only:

then they shall justify the righteous, and condemn the wicked:
acquit the one, whose cause is good, and condemn the other to punishment, who is guilty of a crime, and as that deserves; which is to do righteous judgment; the contrary to this is an abomination to the Lord, ( Proverbs 17:15 ) .