Deuteronomy 17:8-11

8“If any case arises requiring decision between one kind of homicide and another, one kind of legal right and another, or one kind of assault and another, any case within your towns that is too difficult for you, then you shall arise and go up to the place that the LORD your God will choose. 9And you shall come to the Levitical priests and to the judge who is in office in those days, and you shall consult them, and they shall declare to you the decision. 10Then you shall do according to what they declare to you from that place that the LORD will choose. And you shall be careful to do according to all that they direct you. 11According to the instructions that they give you, and according to the decision which they pronounce to you, you shall do. You shall not turn aside from the verdict that they declare to you, either to the right hand or to the left.