The U.S. community of Wolcott, Connecticut, does not have a lot of crime. But when its police chief heard about a chance to provide doorbell cameras to some local homes, he did not wait.

The police force worked with the camera’s manufacturer to give homeowners the devices for free.

The cameras offer a wide field of vision from wherever they are set up. Homeowners get notifications on their wireless phones with video images if the doorbell rings or the device’s sensors observe a person or a passing car.

So far, the cameras have found more wild animals than criminals in Wolcott, a town of 16,000 people. But Police Chief Ed Stephens still likes the idea. “Anything that helps keep the town safe, I’m going to do it,” he said.

But as more police agencies join with the company known as Ring, the partnerships are raising concerns. Ring is part of Amazon, the American technology business.

Critics say that the systems turn neighborhoods into places of non-stop surveillance. They also say the cameras create suspicion that falls heavier on minority groups.

Chris Gilliard is an English professor at Macomb Community College in Michigan. He says Ring and other technologies like it can harden racial barriers.

“Amazon is profiting off of fear,” he said. Part of the plan, he added, seems to be selling the cameras “where the fear of crime is more real than the actual existence of crime.”

Police say the cameras can serve as a digital neighborhood watch. Some police have chosen to simply use Ring’s Neighbors software program, which urges users to share videos of unusual activity.

Other government agencies are offering subsidies or other financial assistance, matched by Ring, on hundreds of discounted cameras.

The California community of Arcadia, near Los Angeles, has spent $50,000 to offer discounts on 1,000 cameras. Several nearby communities take part in similar programs.

Police officers can observe a “heat map” that shows the general area where cameras are set up. But they do not see a camera’s actual position.

If police want a video, they must contact Ring to see if the homeowner is willing to share, said Jennifer Brutus. She works as an analyst for the Arcadia Police Department.

Arcadia started its program at the end of 2017. In the following year, the city reported a 25% decrease in home burglaries, Brutus said.

It is hard to say how much of that is directly related to Ring, but she said the devices do help to reduce crime.

Ring would not say how many communities had such partnerships. Sharing video is always voluntary and privacy is protected, noted the company and police.

Brigid Gorham is a spokeswoman for Ring. “There is nothing required of homeowners who participate in the subsidies, and their identity and data remain private,” she said.

Realistically, though, if police want video for an investigation, they can seek a court’s approval.

Tech industry expert Carolina Milanesi says that working with police is a “very smart move by Ring.” She added that it is a missed opportunity for competitors, including Google’s Nest and smaller companies, such as Arlo Technologies and SimpliSafe.

Back in Wolcott, Ernie Field won a free Ring camera and said he had to register for the software. Now he gets notifications on his phone when cars drive by. And he gets a short video when his daughter comes home from school.

“I don’t know if there’s more crime now, or we just know about it more because of social media,” he said.