Nature's Way

Getting back to the original question. Dr. Thomas W. Shinder, M.D. tells us that "[the] introduction [of syphillis] into the human population is believed to be from sheep that were the original carriers of the disease." He does not tell us how it was introduced and I would rather not think about it too much. It is probably safe to say that if promiscuous sex between human beings leads to the spread of disease, then promiscuous sex with animals does as well. So if it is within the police power of the State to make laws that protect the health of society, it is within the police powers of government to prohibit this kind of sex.