Emerging Surveillance Technologies: Privacy and the Case of License Plate Recognition (Lpr) Technology
Merola, Linda M., Lum, Cynthia, Judicature
An empirical examination of license plate recognition technology and its potential implications for police and courts.
In January 2012, the U.S. Supreme Court decided the case of U.S. v. Jones, which involved the warrantless placement of a surveillance device (a "beeper") on a private vehicle by the police in Washington, D.C. While concealed on the vehicle, the beeper recorded location data over the course of four weeks and, during this time, transmitted more than 2,000 pages of location information to police.1 Ultimately, the Court decided that the warrantless placement of this surveillance device represented an unconstitutional search. To arrive at this conclusion, the five justices in the Jones majority relied upon a theory of trespass grounded in the fact that the police had physically touched the private vehicle to install the beeper and later to replace its battery.2 The remaining justices (while concurring in the judgment) criticized the majority's reliance on this physical encroachment as the basis for the unconstitutional search, instead opting to find an equivalent violation by relying on the well-known Katz "reasonable expectation of privacy" formulation.3
The/ones opinions are striking in terms of the extent to which many ofthe justices manifested awareness ofa need to address privacy issues in the context of surveillance technologies. For example, the concurring justices (those who joined Justice Alito's opinion) included a relatively detailed discussion of devices that have such surveillance capabilities, including CCTV systems, automatic toll devices (such as EZ Pass), automobiles factory equipped with GPS systems, and, of course, smart phones.4 With respect to using technologies like GPS to track the movements of individual automobiles, the concurrence stated unequivocally that, "society's expectation has been that law enforcement agents and others would not [use these devices] to secretly monitor and catalogue every single movement of an individual's car for a very long period."5 A second concurrence, in this case written by Justice Sotomayor, also expressed agreement with this premise, as well as concern over the expansion of law enforcement's surveillance capabilities as a result of technology.6
One technology of this type that has come into widespread use is license plate recognition technology (or "LPR").7 LPR systems use cameras mounted on police cars or at fixed locations to capture and record information about passing vehicles. The systems may be configured in a variety of ways, but LPR readers usually record at least four pieces of information about all passing vehicles: the date, time, and GPS location of a vehicle's observation and the license plate number.8 These systems allow police agencies to automate certain functions, such as checks of passing cars against lists of stolen vehicles or open warrants. However, LPR systems may pose similar concerns to those raised by the Court in Jones because these systems can also afford the police enhanced surveillance capabilities.
After travel data is collected by LPR systems, it may be erased or it may be linked with vehicles' registered owners via state motor vehicle databases and preserved, thereby creating records with substantial details about citizens' daily movements while in their vehicles. As these systems are increasingly deployed, LPR records may eventually contain enough information to allow police to construct a profile of the activities of specific individuals or to recreate individuals' daily movements. Saved data from LPR readers may also be consulted in the future for investigatory purposes or to verify an individual's whereabouts at a particular (past] time.
Despite the momentum toward large-scale data storage by police that is created by LPR, only a relatively small number of articles about the technology have appeared in law reviews or even in the popular media.9 To date, neither have U.S. courts substantively addressed the privacy issues surrounding LPR. …