Law enforcement agents are deploying an onslaught of new technology to collect information on criminals and unsuspecting citizens alike.

Body cameras. Cellphone hacking devices. License plate scanners. Software that can identify faces in surveillance video.

It's all giving authorities in Minnesota and across the country broader and deeper access than ever to data on individuals who often have no clue how information about them is gathered, stored and shared.

But the rapid emergence of such tech tools also is raising alarm about the extent of surveillance — and how laws safeguarding data and guaranteeing public access to it are failing to keep up.

Meanwhile, law enforcement agencies are increasingly reluctant to disclose what's in their high-tech arsenal.

"You have an obvious collision when you have technology moving at the speed of sound and light, and you have a bureaucracy that is constantly behind," said Jim Franklin, outgoing director of the Minnesota Sheriffs' Association.

In September, an assistant public defender in Owatonna asked the Minnesota Bureau of Criminal Apprehension for that information. The agency's response arrived three weeks later: "The BCA confirms that technology fitting the description under [the law] exists at the BCA. Thank you."

Sen. Ron Latz, DFL-St. Louis Park, said the BCA's response flouts the purpose of a 2015 state law requiring disclosure of video, audio, photographic and other monitoring techniques by police. "We didn't want there to be secret technology that was used to surveil the public," said Latz, who has since sponsored a bill with Sen. Warren Limmer, R-Maple Grove, that would require law enforcement to spell out what equipment it is using.

The divisive issue is cutting across party lines at state capitols. Minnesota legislators were concerned enough about safeguards against misuse of cellphone tracking devices that they required police to get warrants to use them, and then make those warrants public.

As of last fall, the courts have kept every warrant secret.

The BCA initially declined to share even its contract with Harris Corp., the maker of the StingRay and KingFish cellphone trackers. The devices mimic cell towers and can capture location data, call logs and in some cases calls and text messages.

The reason for the BCA's reluctance became clear once it released the records in 2014 due to legal pressure. The agency had signed an agreement with the FBI to keep quiet about it, and allowed federal authorities to intervene if anyone inquired about StingRay.

"They don't want all of their toys to be revealed to criminals," said Limmer, chairman of the Senate Judiciary and Public Safety Committee. That equipment has the potential to collect data on law-abiding citizens, so the Legislature has to set limits, Limmer said. "We cannot write policy without knowing what law enforcement has."

Franklin, of the Sheriffs' Association, said Minnesota law appropriately balances the public's need to know with law enforcement's need to safeguard their methods of protecting them.

"If I know the technology that you are using, then I know that I can deploy something around that technology" to defeat it, he said.

The growing covert culture is evident across the country. The New York Police Department has fought in court to hide the details of its fleet of unmarked X-ray vans that can see through buildings and cars. The FBI amassed a facial identification database that now includes 117 million individuals and used it for years without publishing a privacy assessment required by law, the U.S. House Oversight Committee reported in March.

"The transparency is still radically insufficient," said Rachel Levinson-Waldman, senior counsel at New York University's Brennan Center for Justice, who has studied police technology.

Levinson-Waldman said much of the change is driven by influential private companies that develop and market ever-more-powerful technology.

In Burnsville, Police Chief Eric Gieseke presides over a department that was among the first in the nation to deploy body cameras. The department's servers now hold more than 93,000 videos. Almost of them are off-limits to the public, because of a separate 2016 state law that determined that the threat to personal privacy outweighed the benefits of seeing everything a police officer sees.

Gieseke saw its power as a way to enhance accountability during interactions between police and the public. But even he is concerned about some ideas he has heard floated, such as adding facial recognition to body cameras. In theory, the technology could someday ID anybody seen in the footage, allowing officers to know who they are talking to before their first conversation or seeing the person's driver's license.

"When there's new stuff that comes out, let's pause," Gieseke said. Questions about who controls the data, and how long it's kept, need to be worked out first, he said. "It's moving so fast. … Most police departments can't keep up."

High-tech policing

Policing has become a high-tech occupation, even for the rank-and-file. At the start of each patrol shift, most officers boot up a laptop as soon as they slide behind the wheel. The screen displays the feed of the computer-aided dispatch. Each call for help, which officers are assigned, and for those unassigned, how long the callers have been waiting. Officers also use the laptop to look up license plates, warrants and criminal history checks.

The internet also comes in handy. Minneapolis gang members unwittingly help cops by posting status updates on Facebook. Other types of social media come into play too. A homeless guy in Burnsville called 911 in February but didn't say where he was. Officers found him by checking the most recent video in his YouTube channel.

Special cameras mounted on squad cars read the license plate of every car that they see, and instantly check them to see if the vehicle is stolen, or its owner is wanted after a scrape with the law.

Minneapolis police have dashboard cameras and body cameras networked to each other, and they use a smartphone app to give them case numbers and other information. A different app gives officers a direct feed from the ShotSpotter network of gunfire-detecting sensors.

Back at the station, agencies are ramping up their intelligence-gathering to alert officers where trouble could break out, by mining social media. By last August, the Minneapolis police had created 53 undercover social media accounts.

Forensic IT staff, who share tips on the Minnesota High Technology Crime Investigation Association e-mail list, employ software to crack open locked cellphones, restore deleted text messages and photos and work with social media companies to find pedophiles, fraudsters and others who hide behind false identities.

Nowhere has the change been more dramatic than with body cameras. Officers in Minneapolis, St. Paul, Maplewood, Burnsville, Duluth and other departments are now recording each encounter, or will be in the near future. Police stations and precincts are equipped with docking stations with rows of cameras, about the size of a deck of cards, blinking as they upload the officer's video record of a shift and beam it to a distant server.

In November, Minneapolis Police Chief Janeé Harteau announced that all 559 patrol officers would soon be wearing cameras. "This is critical when it comes to transparency," she said. "A second set of eyes are also important for accountability."

Minneapolis took a big step last year with a $4 million contract with Axon, formerly known as Taser International. But a few months earlier, the company landed a contract with the London Metropolitan Police, where officers will be equipped with 22,000 body cameras.

Axon now supplies the cameras and the software, called Evidence.com, to more than half of big-city departments, said Steve Tuttle, spokesman for the Scottsdale, Ariz., company. The devices are generating a "tsunami of data."

Axon has big ideas about how to manage that tsunami. In February, it bought two artificial intelligence companies, and CEO Rick Smith announced that the company could use facial recognition and other tools to make the videos easier for officers to redact faces and voices, and zero in on relevant clips.

Police officers are now video creators, and that could eventually replace traditional written reports, Smith said in February.

"You're the director and producer of your film now," said Burnsville Sgt. Chris Wicklund.

Both Wicklund and his boss, Gieseke, were relieved that the Legislature last year restricted access to the vast majority of body camera video. Even though people who are recorded on videos have the right to see it, only about a dozen people have asked Burnsville for video in the past two years.

Limmer, the state senator, said he expects the Legislature will continue to play catch-up with law enforcement. It started, he said, with a 2012 Star Tribune report that Minneapolis police were storing the data from license plate readers for a year, most of it with no connection to any investigation.

"Every day there's a new invention to find the bad guys. … At the same time, it's accumulating data on law-abiding citizens," Limmer said. "The law enforcement community wants to hold that data as long as possible" in case one of those good citizens turns bad.

New reality

Two days after Maplewood's 52 officers started wearing body cameras, Officer Parker Olding was getting used to the camera magnetically clipped on his chest.

"Everybody's pretty much accepted that's the reality now," said Olding, who's been on the force for three years. "Not long ago, we heard cops angry about body cameras. We've already developed the mind-set over the past couple of years that we're being recorded anyway."

A call came in just after 5 p.m. on a Thursday in February. A mentally ill woman was running amok with a butcher knife. Olding turned on his flashers and sirens and raced to the Maple Pond Homes apartments.

He pressed a button to turn on the camera, bounded up the steps and rapped on the apartment door. "Police."

The woman, wearing only a bra and underpants, sprang up from a couch when Olding told her to stay seated. He held her arms until more officers arrived, and then placed her in handcuffs. Nearby in the kitchen, her ex-boyfriend was bleeding from his wrist.

Another man in the apartment showed Olding his own video of the woman's hourslong outburst, captured on his iPhone. Four officers and two paramedics secured her in a gurney, and then wheeled her out to an ambulance.

Inside, she directed her rage at the Maplewood officers. "You want to shoot me, don't you?" She mentioned Philando Castile, the man killed last summer by a St. Anthony police officer in nearby Falcon Heights.

It's an accusation police officers are used to hearing these days, and they hope the cameras will tell the truth about the peaceful resolution of most service calls. The doors closed, and the ambulance took the woman to the hospital.

Back at headquarters, Olding plugged the camera into its appointed slot, and the video of the "emotionally disturbed person" joined millions of others in the massive vault of Evidence.com.

James Eli Shiffer • 612-673-4116

Twitter: @jameselishiffer