By Eric Tucker, The Virginian-Pilot (Norfolk, VA), The Associated Press

WASHINGTON

Police departments around the country are working to shield their radio communications from the public as cheap, user-friendly technology has made it easy for anyone to use hand-held devices to keep tabs on officers responding to crimes.

The practice of encryption has grown more common, with law enforcement officials saying they want to keep criminals from using officers’ internal chatter to evade them. But journalists and neighborhood watchdogs say open communications ensure that the public receives information that can be vital to its safety as quickly as possible.

D.C. police moved to join the trend this fall after what Chief Cathy Lanier said were several incidents involving criminals and smartphones. Carjackers operating on Capitol Hill were believed to have been listening to emergency communications because they were captured only after police stopped broadcasting over the radio, she said. And drug dealers at a laundromat fled the building after a sergeant used open airwaves to direct other units there – suggesting, she said, that they too were listening in.

“Whereas listeners used to be tied to stationary scanners, new technology has allowed people – and especially criminals – to listen to police communications on a smartphone from anywhere,” Lanier testified at a D.C. Council committee hearing this month. “When a potential criminal can evade capture and learn, ‘There’s an app for that,’ it’s time to change our practices.”

The transition has put police departments at odds with the news media, who say their newsgathering is impeded when they can’t use scanners to monitor developing crimes and disasters. Journalists and scanner hobbyists argue that police departments already have the capability to communicate securely and should be able to adjust to the times without reverting to full encryption. And they say alert scanner listeners have even helped police solve crimes.

“If the police need to share sensitive information among themselves, they know how to do it,” Phil Metlin, news director of WTTG-TV, in Washington, said at the council hearing. “Special encrypted channels have been around for a long time; so have cellphones.”

It’s impossible to quantify the scope of the problem or to determine whether the threat from scanners is as legitimate as police maintain – or merely a speculative fear. It’s certainly not a new concern – after all, hobbyists have for years used scanners to track the activities of their local police department from their kitchen tables.

Rick Hansen says he’s been listening to police communications since he was an adolescent and says efforts to silence them make government less transparent. The Silver Spring, Md., man says sensitive information could be kept off the airwaves on a selective basis.

“Yes, it’s a concern – and it’s something that can be addressed through proper procedures and processes as opposed to turning out the lights on everybody,” he said

There’s no doubt that it’s increasingly easy to listen in on police radios.

One iPhone app, Scanner 911, on its website offers the chance to “listen in while police, fire and EMS crews work day and night.” Apple’s iTunes store advertises several similar apps. One promises to keep users abreast of crime in their communities.

Though iPhones don’t directly pick up police signals, users can listen to nearly real-time audio from police dispatch channels through streaming services, said Matthew Blaze, director of the Distributed Systems Laboratory at the University of Pennsylvania and a researcher of security and privacy in computing and communications systems.

The cost of encryption varies.

The Nassau County, N.Y., police department is in the final stages of a roughly $50 million emergency communications upgrade that includes encryption and interoperability with other law enforcement agencies in the region, Inspector Edmund Horace said. Once the old system is taken down, Horace said, “You would not be able to discern what’s being said on the air unless you had the proper equipment.”

Still, full encryption is cumbersome, difficult to manage and relatively rare, especially among big-city police departments who’d have a harder time keeping track of who has access to the encryption key, Blaze said.