Using wearable video cameras no larger than the size of a deck of cards, Burnsville patrol officers record every traffic stop, every call for help and every major crime from their own point of view.

In a world where everyone with a smartphone is a videographer, the police must adapt, said Police Chief Eric Gieseke.

“The reality is, if we’re not recording ourselves, someone else is,” he said during a demonstration.

A technology that’s only become practical in the past few years, police body cameras that can cost as little as $299 seem likely to arrive at most metro police departments in years to come, even as questions linger about privacy rights, video storage and how and when the cameras get used.

Beyond gathering more foolproof evidence, the cameras have drawn fervent support from those who point to early studies that show the cameras dramatically reduce complaints against police and act as a check against police misuse of authority. If similar results occurred in Minneapolis, a city that’s seen million-dollar police misconduct suits, the cameras would more than pay for themselves.

The idea of adding the cameras there led to a dust-up last week when three City Council members held a news conference promoting them, surprising Police Chief Janeé Harteau, who said more study is necessary. Even as the conversation got off to a muddled start locally, police departments nationwide have taken a strong interest in the technology.

Chest-mounted recorder: Burnsville Police Chief Eric Gieseke showed how an officer wears a chest-style body camera. This is the third year the department has used cameras worn by officers.

At a national police conference last week in Philadelphia, body cameras were a hot topic of discussion, according to Scott Greenwood, a lawyer for the American Civil Liberties Union.

“It is crystal clear that this is the big accountability measure in law enforcement in this point in time,” he said.

A federal judge in Manhattan who struck down the New York Police Department’s stop-and-frisk policy two months ago ordered some New York police precincts to start using body cameras to prevent more violations of citizens’ constitutional rights.

Across Minnesota, Duluth Police Chief Gordon Ramsay told the newspaper there last week that his department will soon use the cameras, joining Burnsville and the Iron Range town of Gilbert, Minn., as early adopters.

“I think that’s what happened is a kind of recognition that citizens are increasingly using iPhones and whatnot to record encounters with the police and police chiefs are thinking, ‘How do we best document what our officers are doing?’ ” said Chuck Wexler, of the Police Executive Research Forum.

The problem is that it’s not as simple as plunking down a few hundred dollars for a camera and pinning it to an officer’s chest, he said.

“The use of a body camera raises a lot of legitimate questions,” he said. When do cameras get turned on, who gets recorded and what’s done with the video once it’s made, for example. If a person wants to tell a patrol officer that they suspect their neighbor is dealing drugs, do they get recorded? And if an officer witnesses someone partially dressed while responding to a call, how do the videos get redacted in preparation for public release?

Wexler said the Police Executive Research Forum is about six months away from delivering a set of body camera guidelines to the U.S. Justice Department.

Cautious approach

It’s those questions that have the Minneapolis Police Department taking a cautious approach, said department spokeswoman Cyndi Barrington.

“Not to say they’re bad, good, right or wrong, there’s just a lot of in-depth research that have to be looked at before moving forward on a project of this size,” she said Tuesday.

Chief Gieseke, of Burnsville, said he understands the go-it-slow approach. He didn’t have detailed data that would show how cameras have changed the department, but said it’s been a generally positive experience as the department built up to 29 cameras since 2010.

The department’s newest camera, from Taser, is worn on the officer’s chest. It has enough battery life to last an extended shift. The officer starts the camera by pushing a big button on the front. The camera keeps a 30-second buffer of video at all times, so each recording starts 30 seconds before the officer presses the button to make sure they don’t miss the start of an incident.

Gieseke said state law doesn’t require the officers to tell people they’re being recorded. Sometimes people will call saying they want to file a complaint against the department, but when they learn that their encounter with an officer is on video, they never show up to file the complaint.

Burnsville officer Shaun Anselment said it’s sometimes a good strategy to announce the camera. “It can calm people down and put them on their best behavior,” he said.

Body cameras got another vote of approval earlier this month when the American Civil Liberties Union broke with its past criticisms of public video surveillance to say proper use of police body cameras benefits everyone.

Worn on ear: Burnsville Police Chief Eric Gieseke demonstrated a different style of body-mounted camera this week. This one is worn over the ear and has a display screen that attaches to the belt. The cameras, used to improve conduct accountability, are slowly catching on in police departments in parts of Minnesota and across the nation.

“We know that the complaints go down and the uses of force go down,” said Greenwood, the ACLU lawyer. He pointed to an oft-cited study of officers in Rialto, Calif., as his proof. A larger study being conducted in Florida has shown similar, though preliminary, results, he said.

The ACLU distributed a policy paper earlier this month that dictates how they think police departments should use the cameras, but whatever gets decided, Greenwood said, one thing is clear: “We are going to start seeing very large agencies implementing this technology in the very near future. It is absolutely inevitable.”