Deuteronomy 21:6-8

Then all the elders of the town nearest the body shall wash their hands over the heifer whose neck was broken in the valley, and they shall declare: “Our hands did not shed this blood, nor did our eyes see it done. Accept this atonement for your people Israel, whom you have redeemed, LORD, and do not hold your people guilty of the blood of an innocent person.” Then the bloodshed will be atoned for