Automatic license plate readers are the most widespread location tracking technology you’ve probably never heard of. Mounted on patrol cars or stationary objects like bridges, they snap photos of every passing car, recording their plate numbers, times, and locations. At first the captured plate data was used just to check against lists of cars law enforcement hoped to locate for various reasons (to act on arrest warrants, find stolen cars, etc.). But increasingly, all of this data is being fed into massive databases that contain the location information of many millions of innocent Americans stretching back for months or even years.
This is what we have found after analyzing more than 26,000 pages of documents from police departments in cities and towns across the country, obtained through freedom of information requests by ACLU affiliates in 38 states and Washington, D.C. As it becomes increasingly clear that ours is an era of mass surveillance facilitated by ever cheaper and more powerful computing technology (think about the NSA's call logging program), it is critical we learn how this technology is being used. License plate readers are just one example of a disturbing phenomenon: the government is increasingly using new technology to collect information about all of us, all the time, and to store it forever – providing a complete record of our lives for it to access at will.
Today, we are releasing all of the documents we have received (accessible through this interactive map and this issue page) and are publishing a report, “You Are Being Tracked,” which explains what these documents say about license plate readers: what they are capable of, how they are being used, and what privacy harms they can cause if protections aren’t put in place. We’re also offering more than a dozen recommendations we think local police departments and state legislatures should follow when they pass laws about this technology.
Check out this great explainer about the technology:
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As is often the case with surveillance technology, there are unobjectionable – even beneficial – uses of license plate readers. We don’t object when they’re used to identify people who are driving stolen cars or are subject to an arrest warrant. But they should not become tools for tracking where each of us has driven.
License plate readers capture vast amounts of data on innocent people
Because of the way the technology works – these devices snap photos of every passing car, not just those registered to people suspected of crimes – virtually all of the data license plate readers gather is about people who are completely innocent. Data that we obtained through our records requests illustrates this point vividly:
Why we should worry
Should the government be logging for months, years, or indefinitely the movements of the other 99 percent of people, who are innocent?
The answer to this question is no. License plate reader information can be very revealing. While one snapshot at one point might not seem sensitive, as blankets of plate readers cover our streets, and as the government stores data for longer and longer, the technology quickly morphs into a powerful tracking tool.
As computer technology and storage capacity get cheaper every year, we need to prepare for a future not just where there are a few license plate reader cameras in every town, but one in which there are multiple cameras on every block.
What can location data reveal about people? Trips to places of worship, political protests, or gun ranges can be powerful indicators of people’s beliefs. Is it really the government’s business how often you go to the drug store or liquor store, what doctors you visit, and the identities of your friends? I’m sure all of us can remember something from our past that could embarrass us. If the government comes to suspect you of something in 2020, should it have access to databases stretching back years that could dig up facts about you that previously went unnoticed?
What's happening now
Law enforcement data-retention policies today are all over the map. While some police departments store data briefly, others keep it for a long time, or indefinitely.
The government doesn’t have a great track record of using this kind of information responsibly. As our report details, the data can be abused for official purposes, like spying on protesters merely because they are exercising their constitutionally protected right to petition the government, or unofficial ones, like tracking an ex-spouse.
Prior to the rise of powerful surveillance technology, it simply wasn’t possible to watch all of the people all of the time. But as these natural limits erode and the impossible becomes possible, we have to make conscious choices about how technology should be used.
What's the right line with license plate readers?
There is a reasonable way to regulate this technology. The primary law enforcement use of these systems is to take pictures of plates to make it possible to check them against “hot lists” of cars of interest to law enforcement. This can be done virtually instantaneously. While plates that generate a “hit” may need to be stored for investigative purposes, there is no need to store plates for months or years to achieve this purpose.
That is to say, the answer to regulating license plate readers is to have strict limits on how long plate data can be retained. While we don’t recommend a specific cutoff date, we think it should be measured in days and weeks, not months and certainly not years.
To their credit, some law enforcement agencies already comply with this principle. For example, the Minnesota State Patrol deletes all data after 48 hours.
Others keep data for longer, and the rationale given is always the same: Although you can’t tell immediately that someone is committing a crime, some of those people may well be doing something wrong, goes the argument. But in our society, the government doesn’t watch all of us all the time just in case we commit a crime.
This is not just an issue we’ll have to decide in the context of license plate readers, but the most important surveillance issue of our time. Should the NSA collect all data about everyone’s calls, just in case it’s useful to identify a terrorist? Why stop there? Why not store all of the contents of the calls we make as well? And emails? This is not just about communications or public movements. It’s also about what happens inside the home. As electric companies convert to “smart grids” that provide them data about the patterns of your electricity usage, it could well become apparent when you take a shower and whether you run your dishwasher more frequently than others in your demographic profile.
License plate readers are just one manifestation of trend. Is this a test case that we can get right?
There is a lot more in the report than I’ve covered in this blog post. Give it a read – I hope you find it thought-provoking. We’ll be posting more blog posts in coming days on different aspects of what we’ve learned about license plate readers. We also invite you to go through the documents yourself. There is more in there than we with our small staff could fully examine, so further newsworthy discoveries may still lurk within, waiting to be discovered. And join us on twitter (hashtag #autotracking) to discuss your finds.
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Press ReleaseDec 2024
Free Speech
National Security
ACLU and Partners Urge Supreme Court to Block TikTok BanACLU and Partners Urge Supreme Court to Block TikTok Ban
WASHINGTON — Today, the American Civil Liberties Union, the Electronic Frontier Foundation (EFF), and the Knight First Amendment Institute at Columbia University filed an amicus brief urging the Supreme Court to block the enforcement of a law that would effectively ban people in America from using TikTok as soon as January 19, 2025. Earlier this month, the U.S. Court of Appeals for the D.C. Circuit rejected TikTok’s challenge to the law. TikTok has asked the Supreme Court for a temporary injunction to prevent the app from being banned while the court considers whether to take the case, saying that unless the justices intervene, the law will “shutter one of America’s most popular speech platforms the day before a presidential inauguration.” “The Constitution imposes an extraordinarily high bar on this kind of mass censorship,”said Patrick Toomey, deputy director of ACLU’s National Security Project. “The Supreme Court should take up this important case and protect the rights of millions of Americans to freely express themselves and engage with others around the world.” The brief argues that the D.C. Circuit failed to fully address the law’s profound implications for the First Amendment rights of the 170 million Americans who use TikTok. While the lower court’s decision correctly recognized that the statute triggers First Amendment scrutiny, it barely addressed users’ First Amendment interests in speaking, sharing, and receiving information on the platform. The court also perplexingly attempted to cast the government’s ban on TikTok as a vindication of users’ First Amendment rights, which it is not. The rights groups also explain that the law was intended to suppress certain content and viewpoints that many legislators believe could be amplified on TikTok, including the risk of foreign “propaganda.” But under the First Amendment, the government must meet a very high bar to restrict speech based on concerns about its “motivating ideology” or “perspective,” and the government has not come close to meeting that bar here. “The government should not be able to restrict speech, especially to the extent here, based on guessing about the mere possibility of uncertain future harm,” said David Greene, civil liberties director at EFF. “The Supreme Court should put the TikTok ban on hold while it considers the DC Circuit’s erroneous ruling.” Finally, the brief underscores that the government can’t impose this type of sweeping ban unless it’s necessary to prevent extremely serious and imminent harm to national security. But the government has not provided evidence of impending harm, or evidence that banning TikTok is the only available way to address its concerns. As the brief explains, the D.C. Circuit improperly treated the government’s invocation of “national security” as a trump card and failed to hold the government to its burden. “Restricting citizens’ access to foreign media is a practice that has long been associated with repressive regimes, and we should be very wary of letting the practice take root here,” said Jameel Jaffer, executive director at the Knight First Amendment Institute at Columbia University. “It would do lasting damage to the First Amendment and our democracy if the Supreme Court let this ban go into effect even temporarily.” You can find the brief online here: https://www.supremecourt.gov/DocketPDF/24/24A587/335380/20241217144322392_24A587%20TikTok%20v%20Garland%20Amicus%20Brief%20pdfa.pdf -
Press ReleaseDec 2024
National Security
Religious Liberty
ACLU Statement on New White House Strategy to Counter IslamophobiaACLU Statement on New White House Strategy to Counter Islamophobia
WASHINGTON – The Biden administration today released the first-ever national strategy to counter Islamophobia and related forms of bias and discrimination, including hate against Arab, Sikh, and South Asian Americans. In advance of the strategy, American Civil Liberties Union and its partners had urged the administration to overhaul government programs that reflect anti-Muslim discrimination. In particular, we have called for urgent action to constrain governmental agencies from continuing to exercise their authorities and technology to wrongly surveil and investigate, watchlist, and question and detain Muslims at the border, as well as deny immigration benefits to people from Muslim-majority countries. While the White House raised expectations that many of these issues would be addressed, the final strategy ended up falling far short. The following is a statement from Hina Shamsi, director of the ACLU’s National Security Project: “While this strategy acknowledges discrimination and its harms, it does little to end them and is a squandered opportunity. For decades, American officials have invoked national security to pass laws and implement programs that disproportionately harm Muslims and people perceived to be Muslim. A serious anti-discrimination strategy would concretely address multiple bias-infused government practices that deny our communities equal participation in civic life and our democracy, like federal watchlisting, surveillance, and investigation. We’re profoundly frustrated that the administration didn’t take even the basic, overdue step of recognizing that anti-Muslim discrimination is uniquely normalized and embedded in government policies.” -
VirginiaDec 2024
National Security
Trabelsi v. Crawford, et al. – Lawsuit Challenging Unlawful Detention and Inhumane Treatment of Acquitted ManTrabelsi v. Crawford, et al. – Lawsuit Challenging Unlawful Detention and Inhumane Treatment of Acquitted Man
Our client, Nizar Trabelsi, is in the United States against his will. The federal government brought him here from Belgium more than a decade ago and charged him with terrorism-related crimes. At trial, the government’s case failed: a federal jury found Mr. Trabelsi not guilty. But instead of allowing Mr. Trabelsi to return to Belgium after his acquittal, the United States placed him in highly restrictive immigration detention and began an ongoing effort to force him to Tunisia, where he was born and where he will very likely be tortured. Mr. Trabelsi’s detention violates the Constitution, immigration law, and the extradition treaty between the United States and Belgium. Through this lawsuit, he seeks to return to Belgium, and he demands an immediate improvement of his detention conditions. -
Press ReleaseDec 2024
National Security
Immigrants' Rights
Federal Judge Rejects Acquitted Man’s Argument That His Immigration Detention Is UnlawfulFederal Judge Rejects Acquitted Man’s Argument That His Immigration Detention Is Unlawful
ALEXANDRIA, Va. — This week, the U.S. District Court for the Eastern District of Virginia ruled that the court does not have jurisdiction to decide whether the government can continue to detain Nizar Trabelsi, a Tunisian national who was brought to the United States against his will for prosecution and was cleared of all charges last year. The ruling means the United States will be able to continue to detain Mr. Trabelsi while it attempts to deport him to Tunisia, where he was born and where, as an immigration judge ruled earlier this year, he will likely face torture. The court also concluded that even if it did have jurisdiction over Mr. Trabelsi’s case, his claims challenging the government’s detention of him would fail. “Reviewing claims that the government is holding someone unlawfully is at the core of the judicial function, and we’re heartbroken for our client that the court got this so wrong,” said Brett Max Kaufman, senior staff attorney with the ACLU’s Center for Democracy. “The government’s arguments in defense of Mr. Trabelsi’s detention makes a hash of the Constitution, immigration laws, and its own extradition treaty.” In 2013, the United States forcibly extradited Mr. Trabelsi from Belgium to face criminal charges in the United States. In July 2023, after almost 10 years of highly restrictive pretrial detention, a federal jury cleared Mr. Trabelsi of all charges. But instead of releasing Mr. Trabelsi or returning him to Belgium, the U.S. transferred him to immigration detention, wrongly treating him as an applicant for admission and placing him in the deportation process. Over the years, the Belgian government has issued multiple formal diplomatic requests asking the U.S. to facilitate his return, but the U.S. has refused to send him back. Mr. Trabelsi filed a lawsuit challenging the government's authority to detain him. He also sought immediate improvements to his detention conditions. Those claims were not part of the court’s ruling today, and will continue to be litigated on a separate track. “Mr. Trabelsi only wants to return to Belgium after being illegally extradited to the United States, held for ten years, and then acquitted by a jury of any crimes,” said Nicole Hallett, clinical professor of law and director of the Immigrants’ Rights Clinic at the University of Chicago Law School. “He cannot be held indefinitely and we will continue to fight to make sure that justice ultimately prevails.” Mr. Trabelsi is represented by the American Civil Liberties Union, the University of Chicago Law School’s Immigrants’ Rights Clinic, the ACLU of Virginia, and Professor Jonathan Hafetz of Seton Hall Law School. The complaint in Trabelsi v. Crawford was filed against Jeffrey Crawford, warden of the Farmville Detention Center where Mr. Trabelsi is being held; Liana Castano, ICE field office director for the Washington Field Office; Alejandro Mayorkas, secretary of the Department of Homeland Security; and Merrick Garland, U.S. attorney general.