Leviticus 16:5-8

And he shall take of the congregation of the children of Israel two kids of the goats for a sin offering, and one ram for a burnt offering. And Aaron shall offer his bullock of the sin offering, which is for himself, and make an atonement for himself, and for his house. And he shall take the two goats, and present them before the LORD at the door of the tabernacle of the congregation. And Aaron shall cast lots upon the two goats; one lot for the LORD, and the other lot for the scapegoat.