A bill introduced in California would allow residents of the state to cover up their license plates while parked to prevent law enforcement from reading the plates with automated license plate scanners.
The bill, proposed by Republican Sen. Joel Anderson, has the backing of privacy advocates, including the Electronic Frontier Foundation, but has come under scrutiny from state police unions.
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License plate scanners, a common piece of equipment used by law enforcement agencies, are able to capture license plate numbers even when a vehicle is moving at a high rate of speed. The scanners record the GPS location, plus the time and date the plate was spotted.
Once it records a plate number, the scanner cross-references the plates with a list of stolen or wanted vehicles. If the plates match a car on the list, law enforcement is alerted and can take action.
Scanners are a tool of convenience for police officers, and can save a significant amount of time in identifying vehicles, but also reveal just how rare it is to stumble across a car on the “hot list.”
The Oakland Police Department revealed it managed to read 793,273 license plates in 16 months with just four scanners, but those scans produced hits in just 0.2 percent of cases — 2,012 hits. That means the majority of those scanned and logged by law enforcement were innocent.
While the scanners may be a powerful tool for police officers, privacy advocates believe the scanners can be used too liberally and create a dragnet designed to capture as much driver data as possible and keep tabs on drivers by storing location data.
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More worrisome to many is not the fact law enforcement agencies have access to the license plate scanners — though there is plenty of concern over how long police maintain records and who exactly they may be tracking — but that private companies do as well.
Vigilant Solutions of California possesses what is believed to be the largest private database of automatic number plate recognition information in the country, with more than 4.5 billion records on file.
“This data puts a wide variety of people at risk,” the EFF wrote in a letter of support for the proposed bill. “The data could be used to stalk domestic violence victims. It could be used to surveil religious centers, law firms, medical centers, gun shows and protests.”
The bill would not allow drivers to obscure their plates while on the road, but would give them the ability to place a cover on the plates while parked. Law enforcement would still have the right to manually move the cover and inspect the plates.
The California Police Chiefs Association has voiced opposition to the bill, filing a letter that argues the proposal would benefit only “those who are trying to evade law enforcement and detection.
The bill comes up for discussion before the Senate Transportation and Housing Committee on May 9.