A little-noticed surveillance technology equips police vehicles with infrared cameras that can record car license plate numbers then log the data for tracking outstanding warrants, suspended licenses and stolen vehicles.
However, the latest crime-fighting tool comes with little-to-no regulation for invasion of privacy.
To give an idea of the power of the technology, called the Data Driver Approach to Crime and Traffic Safety (DDACTs), within the space of two months Denver police vacuumed up 835,000 license plate images leading to 17,000 hits for warrants, stolen vehicles and other things law enforcement searched for.
The license plate readers are three high-resolution digital cameras mounted on a police vehicle for all-round surveillance. The cameras capture license plate images, including information such as date, time and location, and feed them to a laptop with GPS within the vehicle. Using data that is updated every four hours from federal, state and local databases, police can match the plate numbers for wanted vehicles, fugitive warrants, suspended or revoked drivers’ license and stolen cars.
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In a typical use of the technology, a police car will cruise an area of major gang activity or major crime night and day, and record any and every vehicle within the proximity. Detective and field officers are also using the data to identify potential witnesses and suspects for later investigations. Police officials say they also use the data for predicting high traffic-areas that may need special attention and enforcement.
The Denver Police Departmen has become a big advocate of DDACT, which costs $11,000 for each vehicle, according to Forbes. Under Police Commander Paul Pazen, more than 100 officers have been trained on how to the use the technology. The DPD stores the information for 364 day before it is permanently purged.
Other cities like Los Angeles have used the license plate readers for several years, but police officials say adding in links to crime databases increases their effectiveness as drivers are notified when they or their car is wanted.
Privacy advocates like the American Civil liberties Union, though, have been concerned about license plate readers for over three years. In 2012, it sent public records act requests to almost 600 local and state police departments in 38 states and Washington, DC, to find out how the agencies are using the readers.
The group received 26,000 pages of documents in response and realized the readers have the potential to create permanent records of virtually everywhere a person has driven. The ACLU said that the use of this technology is an invasion of privacy as it can reveal what friends, doctors, protests, political events or churches a person might visit.
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Denver Police Commander Pazen told Forbes that concerns about police targeting people is unfounded, since the camera log is so random.
Still, state lawmakers are starting to take action on the license plate readers. Louisiana Governor Bobby Jindal vetoed legislation that would have permitted law enforcement to use the technology to catch stolen vehicles and uninsured drivers.
Gov. Jindal said his decision was due to concerns about the public’s privacy, as such programs “create large pools of information belonging to law abiding citizens that unfortunately can be extremely vulnerable to theft or misuse.”
Other states are passing bills setting limits on how long the data can be retained. Arkansas sets theirs at 150 days, and Minnesota just passed a law that allows law enforcement to hold the data for 60 days unless it is relevant to a crime, with regular audits conducted at law enforcement agencies to ensure that the law is being enforced.