Charles Ellicott Commentary Leviticus 11:39

"And if any beast, of which ye may eat, die; he that toucheth the carcass thereof shall be unclean until the even." — Leviticus 11:39 (ASV)

And if any beast. —That is, a clean animal, which is both cloven-hoofed and ruminant, but which has not been properly slaughtered, having died from any disease or accident. During the second Temple, the law here enacted was restricted to quadrupeds, domestic or wild, but was not applicable to birds and fishes.

He that toucheth the carcase. —The carcass, in this case, is to be regarded as the dead body of an unclean animal , and defiles by contact. (See also Leviticus 17:15.) This, however, only applies to the flesh of the quadruped. The skin, the bones, the sinews, the horns, and the claws are clean, the sacred Scriptures even being written on prepared skins; and the horns used for the trumpets or horns of the sanctuary, according to the canons of the Pharisees, while the Samaritans and the Sadducees regarded them as polluting.