John Gill Commentary Leviticus 20:16

"And if a woman approach unto any beast, and lie down thereto, thou shalt kill the woman, and the beast: they shall surely be put to death; their blood shall be upon them." — Leviticus 20:16 (ASV)

And if a woman approach unto any beast, and lie down thereto , &c.] In order that the beast may lie with her, and solicit it to commit such an action with her, see (Leviticus 18:23).

thou shall kill the woman and the beast : the woman by stoning, and the beast with clubs, as the Targum of Jonathan; and this for the same reasons as before, as well as to prevent monstrous births.

they shall surely be put to death ; both the one and the other, and not spared.

their blood [shall be] upon them ; they are guilty of a capital crime, a crime which deserves death; this must be understood of the man that lies with a beast, and of the woman; for as for the beast itself, as it is not capable of sinning, so not of guilt, in a proper sense.