The bipartisan sponsored bills (SB 699 and HB 289) are designed to limit the use of and storage of information captured by automated license plate readers (ALPR). ALPR systems can capture the license plate number of every passing vehicle and store it in a searchable database. The devices are now commonly used by police throughout the state of Maryland.
ALPR systems came under scrutiny last year when the ACLU reported how the use of devices to record the movements of millions of motorists not convicted of any crime. The ACLU documented how the movements of innocents motorists were being recorded with impunity, and shared with both government and private databases, with few restrictions on how long it could be retained. In most cases agencies do not report where this recording is taking place. In Maryland, the ACLU found that in a five month period of time agencies recorded 1 million license plate, only 0.2% resulted in "hits", almost all of which were for expired registrations. Of the "hits", only 47 (0.0047%) were associated with a serious offense being investigated, and "Furthermore, even these 47 alerts may not have helped the police catch criminals prevent crimes" since the people on the search lists may not have been involved in any present wrongdoing. The vast majority of collected information was for people not suspected of any offense whatsoever.
Additional concerns were raised when in February it was revealed that the Department of Homeland Security was planning to create a national license plate database. After receiving substantial criticism from the press, the agency declared that it was canceling the proposal, however critics have argued that the supposed "cancellation" of the plan is irrelevant since the existence of privately run national databases is already a reality, and the DHS has for years already been accessing this rapidly growing system.
The Boston Globe cited examples of how license plate data had the potential to be misused. In 2005 a Canadian city's police database was improperly used to target a local newspaper columnist in an unsuccessful sting attempt after he had written critical of the city's photo enforcement systems. In 2006 and 2007 the NYPD used ALPR scanners to record worshipers visiting mosques, under a program sponsored by the Drug Enforcement Agency. Washington Post cited an example from 1998 where a DC police officer plead guilty to collecting license plate numbers outside a gay bar and attempting to extort money from the club's visitors. The ACLU noted last year that Virginia has placed ALPR systems outside political rallies.
The proposed bills would forbid law enforcement agencies from retaining captured license plate data (GPS system coordinates, dates and times, photographs of vehicles, and license plate numbers of vehicles) for longer than 30 days unless they were involved in a specific law enforcement investigation, and forbids the sharing of this data except with another law enforcement agency when it is associated with a specific offense.
While this as a fairly weak restriction, the current situation is that there are no restrictions whatsoever on how the scanners can be used or how the data may be shared. But with only a few days left in the session and neither committee having approved a version of the bill, passage of any legislation on ALPR systems this year is becoming unlikely.
UPDATE 4/1/2014: An amended version of this bill has since passed the Senate and is awaiting approval by the House. The amended version removed many of the provisions of the original bill, including limitations on the time which captured plate data may be retained.
Washington Post: A few reasons the public might care about license-plate tracking
Electronic Freedom Foundation: National License Plate Recognition Database: What It Is and Why It’s a Bad Idea
ACLU: Setting the record straight on DHS and license plate tracking
ACLU: Virginia State Police Used License Plate Readers At Political Rallies, Built Huge Database