Thematic Bible: An atonement for murder

If one is found slain in the land which the Lord your God gives you to possess, lying in the field, and it is not known who has killed him, Then your elders and judges shall come forth and measure the distance to the cities around him who is slain. And the city which is nearest to the slain man, the elders of that city shall take a heifer which has never been worked, never pulled in the yoke, read more.
And the elders of that city shall bring the heifer down to a valley with running water which is neither plowed nor sown, and shall break the heifer's neck there in the valley. And the priests, the sons of Levi, shall come near, for the Lord your God has chosen them to minister to Him and to bless in the name [and presence] of the Lord, and by their word shall every controversy and every assault be settled. And all the elders of that city nearest to the slain man shall wash their hands over the heifer whose neck was broken in the valley, And they shall testify, Our hands have not shed this blood, neither have our eyes seen it. Forgive, O Lord, Your people Israel, whom You have redeemed, and do not allow the shedding of innocent blood to be charged to Your people Israel. And the guilt of blood shall be forgiven them. So shall you purge the guilt of innocent blood from among you, when you do what is right in the sight of the Lord.