The American Civil Liberties Union published a study last week looking at information from more than 300 law enforcement agencies throughout the country. The study found the number of license plates being recorded reached more than 10 million.
Law enforcement agencies are snapping photos of your license plate with cameras on their vehicles.
Idaho Falls Police Chief Mark McBride said his department only has one police vehicle with this camera. Bonneville County has another.
"When it's on, it records every license plate that the officer drives by or, if the officer is stationary, every vehicle that drives by the officer," said McBride.
Although less thorough than GPS tracking, plate readers can track where you've been and when, if agencies share photos.
Scanners can be placed on the top of car hoods, on the side of police vehicles or at the top of a cop car. They capture images of parked or moving vehicles. They also record your location. It's then sent to a police database.
The FBI database shows a list of stolen vehicles that will let the officer know whether a car is stolen. Departments can keep the records for weeks or years.
"If they're related to a crime, that information is kept three years past the end of the trial. If they're not needed for evidence, the purge time is 30 days," McBride said.
Cameron Stanford is a lieutenant with the Madison County Sheriff's Office. He said the technology helps them find missing children and people wanted for questioning. It even helped them break up a suicide attempt.
"They happened to come to Rexburg into one of the hotels. One of the cars drove by that hotel and that plate was picked up by the reader. The officers were able to talk to those individuals," Stanford said.
Madison county has four cars with the cameras.
IFPD and Madison County said they will not purchase any more cameras because of cost. Each one has a price tag of about $21,000.
The cameras are paid for through a grant from the Department of Homeland Security.