Deuteronomy 21:6-9

6And all the elders of that city, that are nearest unto him that is slain, shall wash their hands over the heifer whose neck is broken in the watercourse,

7and shall answer and say, Our hands have not shed this blood, neither have our eyes seen it.

8Forgive thy people Israel, whom thou, Jehovah, hast redeemed, and lay not innocent blood to the charge of thy people Israel; and the blood shall be expiated for them.

9So shalt thou put away innocent blood from thy midst, when thou shalt do what is right in the eyes of Jehovah.