Deuteronomy 17:9-12 NIV

9 Go to the Levitical priests and to the judge who is in office at that time. Inquire of them and they will give you the verdict.

References for Deuteronomy 17:9

10 You must act according to the decisions they give you at the place the LORD will choose. Be careful to do everything they instruct you to do.
11 Act according to whatever they teach you and the decisions they give you. Do not turn aside from what they tell you, to the right or to the left.

References for Deuteronomy 17:11

12 Anyone who shows contempt for the judge or for the priest who stands ministering there to the LORD your God is to be put to death. You must purge the evil from Israel.

References for Deuteronomy 17:12