You've likely seen prong collars (like the one pictured above) on dogs in San Francisco — perhaps you've even used one yourself! (On a dog, jeez, what you do in private is your business.) But now SF's SPCA is taking a stand of the controversial devices, by refusing to allow animals wearing them to set foot on their campuses.

As described by the US Humane Society, in a prong collar, "the loop that fits around your dog's neck is made of a series of fang-shaped metal links, or prongs, with blunted points. When the control loop is pulled, the prongs pinch the loose skin of your dog's neck."

According to the Humane Society, "These collars rely on physical discomfort or even pain to teach the dog what not to do. They suppress the unwanted behavior, but they don't teach him what the proper behavior is. At best, they are unpleasant for your dog, and at worst, they may cause your dog to act aggressively and even bite you." However, a quick cyberspace search will show you plenty of presumable dog lovers who are all about prong collars, like this trainer who says "There are very few dogs that I would not train with a prong collar" and this dog rescuer who says that "of all the tools used in dog training, perhaps none is more widely misunderstood and maligned than the prong collar."

Like I said, it's controversial. And now San Francisco's SPCA (which is an independent, community-supported, non-profit animal welfare organization, not to be confused with the city-run Animal Care and Control) has come down on the "against" side of the controversy, and has banned the collars from both of their locations in the city.

It's all part of "a new education campaign about the harm caused by prong collars," SF SPCA spokesperson Krista Maloney says via email.

"Prong collars cause injuries and behavioral problems," the SPCA says in their announcement of the ban, arguing that "prong collars are designed to inflict pain and discomfort and can cause serious physical, behavioral, and emotional damage."

Not only, says the SF SPCA, can prong collars lead to injuries "from skin irritation and punctures to spinal cord problems," but they "often lead to long-term behavioral problems," as "if pain is experienced during everyday activities, like walks and vet visits, dogs can begin to associate an owner's presence, and other harmless stimuli encountered while wearing the prong, with fear and discomfort."

And yet, Dr. Jennifer Scarlett, SF SPCA co-president says, they are still commonly used, as "there's a huge need for community education."

Part of that education will be ending their use on SF SPCA land, as their campuses in both the Mission and Pacific Heights "will become prong-collar-free environments in the coming months." Visitors who arrive with dogs in prong collars will be required to remove the devices while on campus and "instead use flat collars, which will be provided free of charge," the SPCA says.

In addition to the issues Scarlett says the collars cause dogs, they are "a safety concern for our medical staff. Veterinarians and technicians can easily harm themselves while trying to examine a dog who's wearing a prong collar," she says.

It will be interesting to see how this plays out, as even Scarlett admits that use of prong collars is widespread, and "We continue to regularly see prong collars on dogs throughout San Francisco." And many dog guardians that use the collars are passionate proponents, like this one who says that "The very people that speak poorly of prongs are the people that have never actually used them. Isn’t that amazing that they’re so unwilling to leave their comfort zone they’d rather sentence the dog to death by labeling it 'aggressive' than try something that actually works?"

For their part, the SF SPCA appears stalwart in their opposition to the devices. "Despite what some trainers or pet store employees might say, prong collars are not safe or humane," they write on their website.

"There’s no good reason to use them when many humane, effective alternative walking equipment options exist...These collars do nothing to train your dog what behaviors to perform, they only tell him what not to do, using pain and fear."