Deuteronomy 21:4-6

New Century Version

⁴ and they must lead her down to a valley that has never been plowed or planted, with a stream flowing through it. There they must break the young cow’s neck. ⁵ The priests, the sons of Levi, should come forward, because they have been chosen by the Lord your God to serve him and to give blessings in the Lord’s name. They are the ones who decide cases of quarreling and attacks. ⁶ Then all the elders of the city nearest the murdered person should wash their hands over the young cow whose neck was broken in the valley.