We have referred to the television show “NCIS” before, especially with regard to forensic evidence. The show came to mind again when we read about a report released this week by the American Civil Liberties Union. In particular, we thought of all the times we have watched the team scan through images from traffic cameras to track the movements of this week’s terrorist.
Of course, the NCIS team is in the nation’s capital, where security is much tighter than it is here in Raleigh. And these guys are tracking bad guys who are about to blow up the navy yard, not people like us who just want to pick up a little Greek yogurt at the Food Lion.
Well, where NCIS relies on traffic cameras, law enforcement agencies across the country are relying more and more on license plate scanners. And, no, they don’t just track terrorists.
License plate scanners can be mounted on police cars, bridges, light poles and the like. Every time a car passes, the scanner captures an image of the license plate and uploads it to a police database. And there it sits until it is deleted, which could be within six months, as it is in Raleigh, or 18 months, as it is in Charlotte-Mecklenberg, or never, as is the case in Washington County.
Law enforcement agencies explain that they use the images retroactively, not to track people’s movements all day every day. For example, a homicide suspect claims he was at a bar until 11 p.m. Officers pull up the license plate scans from the bar’s parking lot for that time period, and they see that, indeed, the suspect’s car was there.
The ACLU argues back, though, that for all of the data collected, a fraction of them provide useful information. As the organization figured it, about 1 in every 500 license plates qualified as “suspicious.”
The report includes recommendations for government action, including requiring officers to have a reasonable suspicion that a crime has taken place before gaining access to the database. The ACLU also urges states or municipalities to adopt strict retention policies for scans, requiring that records be deleted daily or weekly, barring special circumstances.
If you are wondering if your license plate has shown up in some police database, the ACLU has a recommendation for your benefit, too: People should be able to find out if their own cars’ location history is on file.
Source: American Civil Liberties Union, “ACLU-NC Releases Details of Automatic License Plate Reader Investigation,” July 17, 2013