'Tis the season for private browsing, or so it seems. Apple's Web browser led the pack in introducing a "private browsing mode" in 2005; in recent months, the other browsers on the market have finally followed suit, with Google's recently-released and beta versions of Mozilla and Microsoft similar features.
What does "private browsing" mean, however? For the most part, these "private" modes are designed to protect your privacy only vis-a-vis other users of the same computer, whether you're at an Internet cafe or just trying to avoid letting your partner know what you're doing with their laptop (which earned these features the moniker "Porn Mode"). But do these "private" modes prevent Web sites from identifying you and tracking your actions? If so, how, and how effectively?
Private Browsing and Shared Computers
All of the browsers above offer features designed to protect your privacy vis-a-vis other users of the same computer — preventing others at an Internet cafe, library, or even your home from knowing which Web sites you visited or what information you provided. The mechanism in each browser differs, but the basic concept is the same: none of the sites you visit or the information you provide will be stored in your browser's history or cache, and any are generated will be deleted when you close the browser.
It's worth noting, however, that private modes offer only partial protection. Certain browser extensions, notably the Flash animation player, they are activated — and these cookies are outside of the browser's control. Thus, while a typical user may not be able to retrace your steps, a sophisticated user may be able to do so.
Private Browsing and Internet Sites
Of course, other users of the same computer are far from the only ones who might be interested in your online activities. Web sites and other Internet actors also track behavior for a wide range of purposes. Does private browsing keep their prying eyes away?
One way that Web sites track users is through the use of cookies. All of the new web browsers promise to discard any cookies accumulated while you surf in private mode — but what about the cookies that you've already collected before using private mode? Private mode in new versions of Firefox and Chrome both start "from scratch," ignoring any cookies you may have collected while browsing normally. IE and Safari, however, continues to share any cookies you collected before entering In Private mode.
In addition, sites can use scripts to gather information about Web users. Third-party scripts, which are often used for advertising purposes, pose a particular threat to user privacy, as they allow a single entity to track your behavior across a wide range of Web sites. The only browser to address this situation is the next version of Internet Explorer, which has a feature called "In Private Blocking" that will block scripts that it will block "" IE users will also be able to subscribe to lists of scripts to block, providing an alternate method of identifying and addressing privacy threats.
However, none of these private browsing modes is capable of making your browsing completely "private" by preventing any site from recording your information. Your browser, and your computer, simply don't have that level of control. Web sites can still track you by using your IP address, they can still send and receive cookies within the context of the private browsing session (and many Web sites won't work at all without cookies), and they can still gather, store, and use data that you generate even while browsing "privately." Having a privacy setting on your browser is nice; having a privacy setting for the Web sites you use would be far better.
Private Browsing and User Control
We shouldn't have to "hide" our data from Web sites if we want to remain private; we should simply be able to tell them "don't record this session" and expect our request to be honored. While private browsing modes that use technical measures to protect personal information add value, they only take us so far. Getting Web sites and online businesses to respect our right to control our own personal information is the only way to truly browse privately.
There's a long road to get there, however, and in the meantime, privacy-enhancing techniques like those seen in some of the new browsers are a welcome feature. We hope you'll take the time to tell , , , , and other software developers to keep up the good work. And, of course,we hope you'll continue to support our efforts to upgrade the laws to reflect modern technology, so that "private mode" is the default setting on the Internet.
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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.