Earlier this year, a California woman called 9-1-1 in a panic, begging for help. She’d just checked footage from her home’s doorbell camera and seen a strange person entering the house. When the dispatcher asked her to check the timestamp on the video, it showed that the “intruder” had already been there for 20 minutes without being noticed. That’s when the homeowner realized that she wasn’t in any danger after all, because the stranger shown in the footage was herself.

A few months later, in Indiana, another suspicious resident called police because the live feed from her video doorbell was showing a man on her doorstep. She’d already experienced an earlier incident with a stranger at her door, and had sent police a message about it with the footage from her doorbell camera. When she sent them the new video, they realized the man at her house was a police detective who was there to interview her about the first incident. He was dressed in plain clothes, but wore a badge around his neck that was out of the camera’s sight — although it would have been instantly visible had the resident actually gone to the door.

Incidents like these have critics questioning whether the new age of internet-connected, “smart” home security systems like Ring, Nest and Blink is making crime-fighting easier or harder for cops. Sure, false alarms are an age-old problem, but now citizens can instantly report whatever they find suspicious and send video surveillance of the incident in question with just a touch of a button. One concern is that police may be inundated with more footage than they can handle, without the resources available to watch it all. And much of what they get may be over-reporting of innocent activities, with footage showing people — often people of color — simply walking by or otherwise going about their daily lives.

The ability to constantly monitor neighborhood activity and get round-the-clock notifications from associated apps can also amp up paranoia about public safety. CNET reports that at the International Association of Chiefs of Police conference in May, police from Chandler, Arizona, said that such apps had made residents believe crime was on the rise, even though violent crime statistics were actually at historic lows in their city.

Chandler Police Detective and PIO Seth Taylor told CNET that the department receives at least two alerts a day through the local Neighbors app, typically reporting things that aren’t actually crimes (such as strangers at doorsteps or cars driving past). However, Taylor noted that didn’t mean they aren’t potential leads worth looking into. “Some people are better than others at determining crimes,” he admitted. “But from our perspective, I can tell you that we would be more than happy to investigate all of those.”

Certainly there’ve been many cases where smart doorbells have helped save the day. After all, unlike eyewitness IDs of suspects, which can be faulty, video doesn’t lie. Social media is full of videos showing burglars and porch pirates caught in the act; recently, a doorbell camera in Texas even captured an Amazon delivery driver nabbing a neighbor’s 2-year-old pet dachshund, which she then tried to sell online for $100. And when a woman and her son were found dead inside a Gary, Indiana, home last March, her Ring system was discovered to have recorded video of two possible suspects’ faces. Police identified one of them within hours, and had arrested and charged the culprits four days later. Doorbell camera footage was also used by prosecutors in a Texas capital murder case to show the suspect entering the victim’s home at the time of the killing.

Chandler P.D., which has three officers from its crime prevention unit assigned to watch home surveillance footage and investigate leads, is among the more than 200 U.S. law enforcement agencies that have partnered with Ring (which is owned by Amazon). Some just use the company’s Neighbors app, which allows residents to share their videos of suspicious activity. Others encourage more people to participate in neighborhood watch activities by providing residents with free or discounted cameras with the help of donations and subsidies from Ring. Engaging directly with police has given the company a leg up over its competitors, but it also makes privacy advocates nervous. Ring clarifies that customers can decide who views their footage and must consent before sharing identifying information with police. Officers using the “Law Enforcement Neighborhood Portal” see a “heat map” that shows only the general area where cameras are located, and if they want a video they have to ask whether a resident is willing to share it, or otherwise obtain a warrant.

Such systems can be a boon for departments whose towns don’t have the resources to set up their own surveillance. “We don’t have security cameras citywide,” Mountain Brook, Alabama, Police Chief Ted Cook told GCN. “Essentially, this has the ability of creating security camera technology citywide. We’re asking citizens to participate, to purchase it on their own.”

Rather than partnering with a particular brand, many agencies have their own in-house camera registries, asking residents to sign up their home or business security and surveillance cameras for a database that police can search in case a crime happens nearby, then reach out to those who might have captured relevant footage and be willing to share it. But corporate programs can make it easier to get people involved. In Plano, Texas, police reported that camera registrations went from a couple of hundred on the department’s own system to about 17,000 with Ring.

Regardless of the system, the jury’s still out on how effective this new technology really is. Amazon says a 2015 pilot program in Los Angeles demonstrated that Ring doorbells reduced burglaries by more than half, although a later analysis by MIT Technology Review called that data into question. Arcadia, a Los Angeles suburb, reports that after the first year of its Ring program, it had a 25% reduction in residential burglaries — including one case where a doorbell camera caught footage of four burglary suspects trying to enter a residence, providing the information police needed to identify and arrest the one who initially evaded capture. In addition to helping with arrest and clearance rates, experts say that the sight of doorbell cameras themselves may act as a crime deterrent the way alarm systems do — not just for the house that has one but for the others around it as well.

It’s fair to say that, like license plate readers and facial identification, high-tech home security has its advantages and disadvantages, and as some of the false-report stories show, any “smart” doorbell is only as smart as the humans making use of it. It’s certainly not a final fix for neighborhood crime: Some perps are already well aware of the cams and ways to circumvent them. In a recent burglary case in Sammamish, Washington, where more than $50,000 worth of personal items was stolen from a home, the thieves’ first step was to cut the phone and cable lines, knocking out the house’s Wi-Fi and thereby its alarm and camera system. And in the Atlanta metro area, thieves have just been stealing the smart doorbells themselves, then re-registering and reselling them.

Technology is simply a tool, and it’s one that law enforcement should have access to when and if it’s useful in protecting public safety. But it makes a lot of sense for police to look for innovative ways to coordinate with the communities they serve, share information, and increase the reach of their eyes and ears to enhance security for everyone. After all, as Wolcott, Connecticut, Police Chief Ed Stephens told USA Today in explaining his decision to raffle off doorbell cameras to residents, “Anything that keeps the town safe, I’m going to do it.”