9 And you shall come to the priests, the Levites, and to the judge there in those days, and inquire of them; they shall pronounce upon you the sentence of judgment. 10 You shall do according to the sentence which they pronounce upon you in that place which the Lord chooses. And you shall be careful to do according to all that they order you. 11 According to the sentence of the law in which they instruct you, according to the judgment which they tell you, you shall do; you shall not turn aside to the right hand or to the left from the sentence which they pronounce upon you. 12 Now the man who acts presumptuously and will not heed the priest who stands to minister there before the Lord your God, or the judge, that man shall die. So you shall put away the evil from Israel.
Matthew Henry's Commentary on Deuteronomy 17:9-12
Commentary on Deuteronomy 17:8-13
(Read Deuteronomy 17:8-13)
Courts of judgment were to be set up in every city. Though their judgment had not the Divine authority of an oracle, it was the judgment of wise, prudent, experienced men, and had the advantage of a Divine promise.