Law enforcement nationwide are moving to encrypted scanners, basically blocking anyone from listening in.

Linn County, Johnson County and Black Hawk County are all planning to make the switch this year.

Jason Watts describes himself as a scanner enthusiast, and has several digital scanners.

"I have a few of them around, my wife got me a few of them for my birthday," he said.

But Watts isn't the only one listening.

"We've documented instances where officers have been tracked," Cedar Rapids Police Chief Wayne Jerman said.

That's the main reason Linn County plans to start using encrypted police radios next month, to keep criminals from listening in and possibly targeting officers.

"And there are subjects our officers have stopped that the subjects were involved in crimes or investigations. And these subjects had downloaded the mobile phone app that could allow police radio traffic," Jerman said.

Encrypted scanners also keep personal information, like birthdates and social security numbers from going out on public airwaves.

"There's less chance of identify theft, less chance for HIPPA violation," Linn County Sheriff Brian Gardner said.

But scanner enthusiasts like Watts say the change will not help officers, or those who want to be part of a neighborhood watch.

"While there are criminals that may be able to monitor the scanners, there are also the good people that may be able to give real time information," Watts said.

"We do not need or want people who are not trained law enforcement to arrive on scene of an incident that are armed that could actually danger out deputies are lives in even more in danger than they already did," Jerman said.