If you live in San Francisco and have a dog or a cat, you may be surprised to learn that you are no longer that animal’s “owner.” This week the city finalized a new provision of law that no longer considers pets as personal property. Instead, humans are legally considered “animal guardians.”

Similar changes of law, proposed and lobbied by animal rights organizations including “In Defense Of Animals,” have recently occurred in Boulder, Colorado; in both Berkeley and West Hollywood, California; and in the entire state of Rhode Island. They typically seek to ban the terms “pet” and “owner,” replacing them with “companion animal” and “guardian.” Los Angeles lawmakers recently turned down a like-minded proposal.

This effort parallels the so-called “Sentient Beings” campaign, run by the national animal-rights group Farm Sanctuary and its misguided celebrity spokesperson Mary Tyler Moore. The campaign is going from town to town in at least 12 states, asking city councils to adopt resolutions declaring livestock exempt from “inhumane” treatment (including, of course, the act of being eaten). So far, cities in California, Florida, New Jersey, and Ohio have signed on.

Duane Flemming, president of the American Veterinary Medical Law Association, told the Los Angeles Times last year that these trends are setting a “dangerous precedent… This is a slippery slope. It is a very dangerous situation. The real, true, underlying sub-goal is to ultimately change people’s perceptions, all the time heading toward the concept of getting legal standing. Once you can do that, the animal-rights people can change the fabric of our nation.”