What that means is news outlets and the general public will no longer be able to hear when a traffic accident blocks a major intersection or an armed standoff results in evacuations.
The Wilmington, N.C., Police Department made the changeover in January and the New Hanover County Sheriff's Office is in the process of doing the same.
"Over the last couple of years we've seen an increase in criminal activity using technology to monitor law enforcement channels," said Sgt. Jerry Brewer of the New Hanover County Sheriff's Office. As an example, Brewer told of a time during a vehicle stop when he heard a deputy's call to dispatch echoing from a scanner under the driver's seat of the stopped vehicle.
"For officer safety we feel it's necessary to encrypt our channels," he said.
Brewer, the sheriff's office spokesman as well as department's communications technician, said the changeover to encryption involves no additional costs for agency.
"When we purchased the radios six years ago they came with encryption software. We are now going in and enabling that encryption," he said.
The software then scrambles the transmissions and only radios that have the software installed will be able to unscramble or "decrypt" the communication.
Wilmington Police Chief Ralph Evangelous also cited officer safety as the reason for making the change to encryption in his department.
"With growing technology, criminals are now able to monitor our movements better than before. We will take every measure to ensure our officers have clear and safe communications," he said.
Evangelous said the change will not affect officer response times.
Media rights attorneys argue against encryption, seeing it as preventing access to public records.
"If you look at the (N.C. statute) you have a right of access to information transmitted over the public airwaves," said Amanda Martin, general counsel to the N.C. Press Association. "I would argue they have to release the encryption key so that the public can assess that.
"If you're driving your car down the interstate and you have your doors locked or you're driving your car down the interstate with the doors unlocked, you're still on the interstate."
The law Martin refers to is N.C. General Statute 132, which governs, among other things, access to public records.
Under the statute, law enforcement has a right to withhold certain information vital to an ongoing investigation, but "the contents of communications between or among employees of public law enforcement agencies that are broadcast over the public airways" are specifically listed as open to the public.
"Scanners were around when the law was written, so it's pretty clear that the legislature wanted us to have access to communications between law enforcement agencies," Martin said.
Brewer said the move isn't aimed at preventing access to public records.
"We're not taking away your right to listen to radio traffic, you just have to request those records from 911 now," he said.
While Brewer admits the change could hinder some communication between departments without encryption, he said those agencies need only have their radios programmed to listen to sheriff's office's activity. Getting a radio programmed is not an option for the general public, however.
Brewer said in the event of an incident in which New Hanover deputies need to communicate with other entities, they can still switch to open public safety channels or communicate via VIPER, a radio system used to connect emergency personnel statewide.
Law enforcement encryption is an understandable sign of the times, said Warren Lee, director of New Hanover County Emergency Management and 911 Communications.
"There are a lot of people out there who have access to scanners and they are tracking every move," he said. "They certainly don't want situations where an officer is responding to something and somebody is waiting there ambushing him."
Lee said scrambled radio traffic won't affect the dispatch center since its radios also came equipped with the encryption software.
Wilmington Fire Department Battalion Chief David Hines said the change has little bearing on WFD's operations.
"There's no plans for us to encrypt ... and we don't have many incidents where we're talking to (law enforcement) on the radio," he said. "We don't see it as an issue."
For police scanner buffs whose background music is the ever-present cacophony of tones, calls signs and sirens, the silence will be deafening.
"This means we're going to have a more difficult time in getting a heads up. Obviously we use those scanners to stay ahead of things and react as quickly as possible," said Kevin Wuzzardo, news content manager with Wilmington's WWAY NewsChannel 3. "Without (scanners) we're going to have to rely more on official releases, and then you're only getting the news that law enforcement wants you to get.
"The question is, how do you balance the First Amendment with personal safety? If it were up to us journalists, we'd always want it all available."
(c)2014 the Star-News (Wilmington, N.C.)