WOODBRIDGE, Va. — Automatic License Plate Readers are once again about to be the center of a debate in Richmond.

The readers, or ALPRs, are mounted to the rear of police cars and are equipped with high-speed cameras that capture license plates. Those photos are then processed by a computer, and the letters and numbers on the license plates are then cross-checked on a list of vehicles that have been reported stolen. If the ALPR returns a hit on a stolen car, the police officer can then pursue the driver and then could make an arrest.

Police in Prince William County say ALPRs have become a useful tool in their fight against crime.

ALPR data was used in a case where multiple larcenies from auto had taken place. A license plate number was provided but did not return as valid through Virginia. A query of the ALPR database showed the vehicle returned to a particular location. A check of the same area resulted in the suspect being located and the stolen property recovered. Additionally, a hit and run suspect was similarly located when his license plate returned to an Alexandria address. A check of the ALPR database showed local entries. A check of one of those areas resulted in the location of the suspect. ALPR technology was also utilized to help identify and arrest the suspect involved in the shootings of the Marine Corps Museum, Pentagon and Coast Guard Recruiting Center. — Prince William police spokesman Jonathan Perok

Prince William police hold onto the license plate data captured for up to six months unless the data is used in a criminal case, and then it’s kept on file longer.

Two locally elected leaders from both sides of the aisle, Virginia State Senator J. Chapman Petersen (D-Fairfax) and Delegate Richard Anderson (R-Prince William) are set to hold what they’ve dubbed the “Benjamin Franklin Privacy Caucus.” Both legislators have introduced bills addressing the use of ALPRs, and both have delayed their bills until the upcoming legislative session in Richmond in January to “permit consultation with law enforcement officials and citizen groups.”

The caucus takes its name from Franklin’s saying “they who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety,” according to the legislators hosting the event.

It will take place in House Room 3 of the Virginia state capitol building on Tuesday, Sept. 23, from 2-4pm. Anyone is able to attend and speak.

“We must strike a reasonable balance between the crime fighting tool that this technology represents and the privacy and other Constitutional rights of citizens in Prince William County and across Virginia,” stated Anderson in a press release. “My bill, which I submitted in 2014 and delayed until 2015, reflects the views of our Prince William neighbors and will specify a reasonable rule set for the use of this new technology.”

Police say the ALPRs capture only information on license plates, something that is already in public view at all times.

There is no personal information obtained through the use of the ALPR system, therefore no invasion of privacy. The ALPR system only captures pictures of state issued vehicle license plates with the location and date/time of where the plate is captured. Any further information on the vehicle itself and/or its owner must be obtained through a separate query through the DMV and/or VCIN. Such queries are restricted by Virginia law and may only be performed for legitimate law enforcement purposes. It should be noted that license plates are in public view for all to see and anyone can easy capture a plate with a cell phone or other camera. The ALPR system simply allows us to capture more license plates quickly and automatically. – Prince William spokesman Jonathan Perok

These days, license plate readers are being used for more than law enforcement purposes. In Florida, where many of the state’s toll roads no longer have manned toll booths and accept only cash-less forms of payment, a system called “toll-by-plate” is in use.

The arrangement allows drivers without a electronic transponder in their car that can be linked to a credit card, to be sent a bill for the toll to the address where the license plate is registered.