![](https://www.eff.org/files/2014/01/27/alpr2_0.png)
We have also argued, though, that the only way to have an informed public debate about appropriate limits on ALPRs is through greater transparency about how the technology is actually being used. This is why we’ve asked for a week’s worth of data collected by all of LAPD and LASD’s ALPR cameras, in addition to policies and procedures on how the agencies say they’re using the technology. It isn’t possible to know what police are really doing until we have at least a representative slice of the data they collect.
A nationwide privacy problem
![](https://www.eff.org/files/2014/01/27/alpr_monitor.jpg)
Already many agencies have created massive databases that record the travels of millions of drivers in a city, region or state. According to the LA Weekly, LASD and LAPD “are two of the biggest gatherers of automatic license plate recognition information,” logging 160 million data points, an average of 22 scans for every one of the 7 million vehicles registered in Los Angeles county. Agencies also share data, so that, for example, LASD can query license plate data from 26 other police agencies in Los Angeles County and is working to expand its reach to Riverside and San Bernardino counties.
The data can trigger instant alerts if a scanned plate is associated with a crime, is on a stolen vehicle list or meets other criteria. Departments, and even individual units, can also create their own “hot lists” so that ALPR users will be alerted whenever a “vehicle of interest” is located. Officers can also enter individual plates into their ALPR system to be searched for during that shift. Officers don’t seem to need reasonable suspicion (much less a warrant) before adding plates to these “hot lists,” and LASD’s own records note that the hot lists don’t automatically provide “sufficient justification to pull over ordetain vehicle occupants.”
Why ALPRs need limits
Without proper safeguards, ALPR technology can harm privacy and civil liberties. A network of readers enables police to collect extensive location data on an individual, without his knowledge and without any level of suspicion. ALPRs can be used to scan and record vehicles at a lawful protest or house of worship; track all movement in and out of an area; specifically target certain neighborhoods or organizations; or place political activists on hot lists so that their movements trigger alerts. In U.S. v. Jones, Supreme Court Justice Sonia Sotomayor noted the sensitive nature of location data and the fact that it can yield “a wealth of detail about [a person’s] familial, political, professional, religious, and sexual associations.” Taken in the aggregate, ALPR data creates a revealing history of a person’s movements, associations and habits.
![](https://www.eff.org/files/2014/01/27/rybak_0.png)
How transparency can protect your rights
Police tracking of the public’s movements can have a significant chilling effect on speech and civil liberties. The International Association of Chiefs of Police has cautioned that ALPR technology “risk[s]… that individuals will become more cautious in the exercise of their protected rights of expression, protest, association, and political participation because they consider themselves under constant surveillance.” And researchers have documented how NYPD surveillance of Muslim communities created a “pervasive climate of fear and suspicion that encroaches upon every aspect of [community members’] religious, political, and community lives.”
Public records requests like ours are having an impact on police use of ALPRs. In Minneapolis, the Star Tribune story about ALPR technology began with a public records request and led to a debate about policy changes on data retention, with legislators recognizing the privacy interests implicated by ALPR data collection and advocating for an end to law enforcement retention of location data on non-criminals. Similarly, after a public records request revealed that the Boston Police Department was misusing its ALPR technology, the Police Department “indefinitely suspended” its ALPR use.
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The very real risks to privacy and civil liberties posed by ALPR require public understanding of how police departments use this technology. Without public access to information about how ALPR technology is being used, the very people whose whereabouts are being recorded cannot know if their rights are being infringed nor challenge policies that inadequately protect their privacy. We will continue to push for records in this case and to encourage legislatures to pass legislation—like Michigan’s and Massachusetts’—that has teeth and provides meaningful limits on the collection, retention and sharing of license plate data.
Our brief and accompanying declaration and exhibits are below.
— ACLU SoCal & EFF — License Plate Readers - Opening Brief
— ACLU of SoCal & EFF — License Plate Readers - Declaration & Exhibits
Peter Bibring is senior staff attorney at the ACLU of Southern California and Jennifer Lynch is senior staff attorney at the Electronic Frontier Foundation.