Deuteronomy 17:6-9 New American Standard Bible (NASB)

6. On the evidence of two witnesses or three witnesses, he who is to die shall be put to death; he shall not be put to death on the evidence of one witness.

7. The hand of the witnesses shall be first against him to put him to death, and afterward the hand of all the people. So you shall purge the evil from your midst.

8. "If any case is too difficult for you to decide, between one kind of homicide or another, between one kind of lawsuit or another, and between one kind of assault or another, being cases of dispute in your courts, then you shall arise and go up to the place which the Lord your God chooses.

9. So you shall come to the Levitical priest or the judge who is in office in those days, and you shall inquire of them and they will declare to you the verdict in the case.

Deuteronomy 17