Deuteronomy 21:4 ASV

²  then thy elders and thy judges shall come forth, and they shall measure unto the cities which are round about him that is slain:

³  and it shall be, that the city which is nearest unto the slain man, even the elders of that city shall take a heifer of the herd, which hath not been wrought with, and which hath not drawn in the yoke;

⁴  and the elders of that city shall bring down the heifer unto a valley with running water, which is neither plowed nor sown, and shall break the heifer's neck there in the valley.

⁵  And the priests the sons of Levi shall come near; for them Jehovah thy God hath chosen to minister unto him, and to bless in the name of Jehovah; and according to their word shall every controversy and every stroke be.

⁶  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;