Sforno on Leviticus 16:9/ספורנו על ויקרא ט״ז:ט׳

1ועשהו חטאת, the lot determines which of the male goats is to be the sin offering for the altar. In the words of our sages (Yuma 40) “the lot determines which is the sin offering, and not the name.” [calling it such is meaningless unless confirmed by the lot drawn. Ed.]