Deuteronomy 21:6-8

And all the elders of that city, who are nearest unto the slain man, shall wash their hands over the heifer whose neck was broken in the valley; and they shall answer and say, Our hands have not shed this blood, neither have our eyes seen it. Forgive, O Jehovah, thy people Israel, whom thou hast redeemed, and suffer not innocent blood to remain in the midst of thy people Israel. And the blood shall be forgiven them.