As of Thursday morning local time, a San Francisco animal adoption agency will immediately halt its recent use of a controversial security robot.

The move comes after the San Francisco SPCA had been scrutinized for its deployment of a Knightscope K9 to mitigate vandalism and the presence of homeless people at its Mission District office. Knightscope, a Silicon Valley startup, declares on its website that its robots are the "security team of the future."

That robot made headlines when Business Insider reported Tuesday that "Robots are being used to deter homeless people from setting up camp in San Francisco."

Dr. Jennifer Scarlett, president of San Francisco's SPCA, said the following in a statement sent to Ars on Thursday morning:

Although we had already limited the use of the robot to our parking lot, we think a more fully informed, consensus-oriented, local approach on the appropriate use of these new devices will benefit everyone—whether it's on public space or in private parking lots... We welcome guidance from the city on policies for the use of autonomous security robots. Since this story has gone viral, we've received hundreds of messages inciting violence and vandalism against our facility and encouraging people to take retribution. In addition, we've already experienced two acts of vandalism on our campus.

An entrenched problem

The SF SPCA's main facility sits at 201 Alabama Street, in a section of the city that has been undergoing rapid gentrification for well over a decade. What was once a largely working-class Latino neighborhood has now given way to the heart of hipster San Francisco—a new Alamo Drafthouse opened just last year. Rents have skyrocketed. Homeless people routinely congregate near the Mission’s two BART stations.

In this particular section of the Mission, however, there are not only individuals but pitched tents and other makeshift shelters on public sidewalks very near the SPCA office.

When Ars turned up at the SPCA's office unannounced on Tuesday afternoon, we saw no Knightscope K9 rolling robot anywhere near the main entrance. We also saw no evidence of any homeless people or encampments in the immediate vicinity of Alabama Street.

Knightscope rents the robots to companies ranging from Microsoft to the Sacramento Kings. The company touts them as a supplement or replacement to human security guards—they only cost $6 per hour. The egg-shaped droids provide constant video surveillance and an imposing, moveable physical presence.

Earlier this year, Ars reported on an incident in which a Knightscope robot was attacked.

The company did not respond to Ars' request for comment.

Vandals!

When Ars asked the SF SPCA about the robot on Tuesday afternoon, spokeswoman Krista Maloney explained that her organization had recently experienced "a great deal of car break-ins, theft, and vandalism."

In an email, she explained why the robot was needed:

Over the summer, our shelter was broken into twice... The inside was vandalized, and property and cash donations were stolen. This was a major safety concern, particularly for our overnight veterinary staff. Furthermore, many staff members and volunteers have filed complaints about damage to cars and harassment they experienced in our parking lot when leaving work after dark. We currently employ security guards, but we have a large campus, and they can only be in one area at a time.

Maloney also said that, due to the robot, the agency had "seen a significant decrease" in petty crime and vandalism, calling it "very effective."

Maloney also said that the robot "predicts and prevents crime," and she noted that it recorded video around the clock, "and evidence of vandalism or other crime is sent to the San Francisco Police Department."

Ryan Calo, a law professor at the University of Washington who studies robotics, said that there is no clear evidence that Knightscope's robots can, in fact, predict or prevent crime. He also said that the $6 per hour fee is "arbitrary" and suggested that Knightscope may be setting it artificially low.

"They're the only game in town," Calo said. "Of course, they have every incentive at the early stages to set [Knightscope's price] low enough that makes it look like they're cheaper than security guards. There [are] often human beings that are in the background."

But beyond the economics, he was concerned that the SF SPCA had even taken this step for just a short month.

"How do we come to a place in society where we are herding people with robots instead of treating people with dignity and respect?" Calo said. "It's a small step from a situation where robots are keeping an eye on things and then they need to call for backup. There's a small distance between that and having them intervene."

Similarly, Linda Lye, an attorney at the American Civil Liberties Union of Northern California, told Ars that the use of such robots was a "troubling example of how invasive new surveillance technology is deployed in ways that disproportionately harm vulnerable communities."

Another law professor at Vanderbilt University, Christopher Slobogin, who has worked on "panvasive" surveillance technology, told Ars that these robots are perceived as being more intrusive than traditional CCTV cameras.

"It's just that the robots are more noticeable—more like humans—and thus are perceived as more intrusive than a camera on a pole," he emailed.

In the month that the robot was deployed, the SPCA's Maloney also said the robot's presence had not resulted in any arrests or prosecutions. But she again highlighted a "significant decrease in the amount of crime on our campus."

Maloney added that the reason why we did not see the robot when we visited earlier in the week was that it was only set up at the office's rear parking lot. She did not immediately respond to our further query as to whether the robot would be returned to the Mountain View startup.

"We piloted the robot program in an effort to improve the security around our campus and to create a safe atmosphere for staff, volunteers, clients, and animals," Dr. Scarlett wrote in the statement. "Clearly, it backfired."

"We sincerely hope our robot pilot program does not overshadow the incredible work our staff and volunteers do to serve animals and people—all people, regardless of their living circumstances. We are also hopeful that it has drawn attention to the challenges facing the homeless, a problem that needs all of our attention."

UPDATE 5:41pm ET: In an e-mail to Ars, Knightscope spokeswoman Donna Michaels provided this statement: "Contrary to sensationalized reports, Knightscope was not brought in to clear the area around the SF SPCA of homeless individuals. Knightscope was deployed, however, to serve and protect the SPCA. The SPCA has the right to protect its property, employees and visitors, and Knightscope is dedicated to helping them achieve this goal. The SPCA has reported fewer car break-ins and overall improved safety and quality of the surrounding area."

She did not immediately respond to further questions.