Deuteronomy 21:6-9

21:6 and all the elders of that city nearest the corpse must wash their hands over the heifer whose neck was broken in the valley. 21:7 Then they must proclaim, “Our hands have not spilled this blood, nor have we witnessed the crime. 21:8 Do not blame your people Israel whom you redeemed, O Lord, and do not hold them accountable for the bloodshed of an innocent person.” Then atonement will be made for the bloodshed. 21:9 In this manner you will purge out the guilt of innocent blood from among you, for you must do what is right before the Lord.