​Six weeks after the U.S. Supreme Court’s 6-3 opinion in Chatrie v. United States, it is just now becoming clear what a breakthrough opinion it actually was.

This ruling leaves an altered legal landscape, one in which courts have fresh opportunities to apply stringent constitutional scrutiny to many intrusive technologies, ranging from automated license plate readers to internet search histories.

At first, this ruling struck many legal observers as a welcome but modest expansion of Fourth Amendment law. Basing its conclusions on recent precedents, the Court held that whenever the government uses a geofence warrant to pinpoint an individual’s location history through cellphone data, it is performing a Fourth Amendment search.

Stanford Law School professor Orin Kerr has now written a sharp analysis contending that Chatrie’s apparently narrow ruling is, in fact, a “blockbuster” that offers the most “rhetorically broad vision of the Fourth Amendment” in 140 years. We think he is right.

Kerr writes that Chatrie “is an expansive pro-privacy opinion that advances new principles and throws into question a wide range of existing surveillance practices.”

The Principle of Consumer Perception

Much of Chatrie’s majority opinion was grounded in precedent, such as Carpenter v. United States. This 2018 ruling held that a warrant is required to track a person’s location history, while limiting that standard to location data collected from cell towers.

“But a close look shows that Chatrie recasts precedents at every turn,” Kerr writes. “Chatrie alters the applicable approaches, adopts new standards, and drops old distinctions.”

For example, a generation ago, the Fourth Amendment was widely understood to prohibit authorities from searching property and “effects” inside a home, a car trunk, or a suspect’s pockets without a warrant based on probable cause. Outside those protected spaces, authorities were – and are – generally free to tail people or rifle through their garbage.

Chatrie demolished this inside/outside distinction. Data held in the cloud can now enjoy a level of protection similar to that of a document in a desk in one’s home. Another way Chatrie goes beyond Carpenter is by bringing users’ perceptions into the equation. Kerr writes:

“It appears that a typical user’s perception of connection with data – generally a matter of app design and interface – can govern whether there are Fourth Amendment rights in the data after the data is disclosed.”

The Intimacy of Data as a Factor
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Kerr notes that the ruling introduces new concepts into Fourth Amendment law, holding that data generated by ordinary activities on cellphones cannot be presumed to be voluntarily disclosed to third-party tech companies. And Chatrie reorients Fourth Amendment law around the intimacy of private information, rather than the manner in which it was obtained.

Kerr quotes Justice Sonia Sotomayor’s concurrence in a prior case, in which she noted that GPS records contain a “comprehensive record of a person’s public movements that reflects a wealth of detail about her familial, political, professional, religious, and sexual associations.”

This reasoning from one justice in a 2012 case about GPS seems to have filtered into the majority’s thinking about technology in general.

What’s Next?

Where does the law go from here? Some courts will undoubtedly interpret Chatrie narrowly, restricting it to location data. Doing so, however, would ignore the broader implications of Justice Kagan’s majority opinion and its new standards.

We can expect conflicting rulings as lower courts try to apply Chatrie to automated license plate readers, tower dumps, IP addresses, subscriber information, internet search terms, blockchain transactions, and online undercover operations.
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If lower courts are true to Chatrie, they will recognize a constitutional imperative to apply the Fourth Amendment to curb the unprecedented power of new technology to expose the entirety of a human life. 

​The U.S. Supreme Court’s landmark decision in Chatrie v. United States settled one important question while raising another that Congress can no longer ignore.

If the government needs a warrant to compel Google to disclose Americans’ location records, why should it be able to sidestep that requirement by buying the same records from a data broker?

Chatrie’s Principles

In a 6-3 opinion, the Court held that Americans retain a reasonable expectation of privacy in detailed cellphone location records, even when those records are held by a third party such as Google. Police therefore conduct a Fourth Amendment search when they compel disclosure of that information through a geofence warrant. 

In writing the majority opinion, Justice Elena Kagan recognized a simple truth about modern life: carrying a smartphone inevitably generates an extraordinarily revealing record of where we go, whom we visit, who our romantic partners are, which churches we attend, what political rallies we join, and countless other intimate details. Americans do not surrender their constitutional privacy merely because technology companies necessarily store that information. 

But if that is true, an obvious question follows: Why allow the federal government to simply purchase the very same information from a commercial data broker?

The Data Broker Loophole

Today, at least a dozen federal agencies have acknowledged buying commercially available personal data. These include the FBI, the Drug Enforcement Administration, the IRS, the Department of Homeland Security, the Department of Defense, and elements of the intelligence community. Instead of obtaining a warrant approved by a judge, these agencies often obtain access simply by writing a check.

This practice has become known as the “data broker loophole,” a gaping privacy vulnerability that turns the Fourth Amendment inside out.

Suppose police could not constitutionally enter your home without a warrant, but could legally pay your neighbor to climb through the window and photograph every room. Few Americans would believe the Constitution permits such an end-run around judicial oversight. Yet that is effectively what has developed in the digital age.

Commercial data brokers aggregate astonishing quantities of personal information collected by smartphone apps, advertisers, financial transactions, connected vehicles, and countless online services. These databases can map a person’s movements, habits, religious observance, medical concerns, political associations, and relationships with extraordinary precision. Agencies can often acquire such data without ever demonstrating probable cause to a court. 

Now, Chatrie pokes holes through the government’s thin rationale by holding that highly revealing location histories remain constitutionally protected even when maintained by private companies.

If the Constitution bars the government from compelling disclosure without a warrant, Congress should not permit agencies to obtain the same information merely because a private intermediary has placed it on the market.

The bipartisan Fourth Amendment Is Not for Sale Act would close this loophole by requiring government agencies to obtain a warrant before acquiring sensitive commercially available data. The core provisions of that legislation should be incorporated into Section 702 of the Foreign Intelligence Surveillance Act when it comes up for reauthorization.

The Supreme Court now recognizes that Americans possess a reasonable expectation of privacy in the digital trails their smartphones inevitably create.
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Congress should finish the job by closing the data-broker loophole when it reauthorizes Section 702.

​When your daily movements are tracked by your cellphone, you likely have an intuitive sense that this is your private information, even if it is shared with Google or Apple.
 
The Supreme Court made that common perception a principle on Monday.
 
In a 6-3 decision in Chatrie v. United States, the Court ruled that you do, indeed, have an expectation of privacy against government intrusion as your mobile devices track your movements throughout the day.
 
Based on a Solid Precedent
 
Monday’s ruling strengthens and extends a principle established by the Court in Carpenter v. United States (2018), which found that law enforcement needs a probable cause warrant to obtain cellphone users’ daily movements from cell towers.
 
In Chatrie, in which police conducted a broad search of many people’s location histories in order to catch a bank robber, the Court is now setting a broad principle that promises to extend to cases regarding other forms of data held by companies in the cloud.
 
The Court found that Google’s Location History “resembles other private materials – think of emails, documents, photographs, or calendars – that even if stored on Google’s servers, a user reasonably views as his own. And as a result, that he reasonably expects to be shielded from the ‘inquisitive eyes’ of the government.”
 
How We Got Here
 
The Court had to weigh the implications of Carpenter against the Fourth Circuit’s finding that the defendant “did not have a reasonable expectation of privacy in two hours’ worth of Location History data voluntarily exposed to Google.”
The majority opinion declared that the comparisons between Location History and cell-site tracking “practically leap off the page.” Cell-site tracking places an individual within one-eighth to four square miles. Google’s Location History placed Chatrie within twenty meters. In addition to this data’s precision, the Court noted the government can retrospectively construct the movements of cellphone users, effectively placing them under surveillance before they can even think of committing a crime.
 
Monday’s majority opinion reiterated the Court’s observation that modern cell phones are “such a pervasive and insistent part of daily life that the proverbial visitor from Mars might conclude they were an important feature of human anatomy.”
 
Justice Kagan’s Majority Opinion
 
Overall, the government contended that cellphone users voluntarily relinquish their data, that constitutional concerns should be applied on an app-by-app basis, and that the search was too brief to be constitutionally significant.
 
Justice Elena Kagan penned the majority opinion, which bitingly dissected each of the government’s arguments, starting with the assertion that our data sharing is voluntary. Justice Kagan noted that Google repeatedly prompts users to enable Location History. She wrote:
“The first prompt comes when a user initially establishes a Google account. If that spur is ignored, another will arrive when a user sets up a Google app – like Google Assistant, Google Maps, or Google Photos – on his phone or other device. Android (though not iPhone) users are specifically warned that their devices will not ‘work correctly’ unless they turn on Location History.”
 
What about the government’s claim that law enforcement accessing Location History should receive a Fourth Amendment “grace period” of some number of hours? Justice Kagan sardonically referred to this short grace period of a few hours as a “Constitution-free zone.”
 
At risk, she wrote, were “trips that a person is apt to think ‘indisputably private’ to the psychiatrist, the plastic surgeon, the abortion clinic, the AIDS treatment center … or the criminal defense attorney.”
 
Justice Kagan’s analysis tracked PPSA’s amicus brief, in which we held that “where the Fourth Amendment applies, it applies regardless of ‘the quality or quantity of information’ the government obtains.”
 
Justice Kagan also turned to how cellphone technology is actually used today to demolish the government’s idea of analyzing the constitutional implications of a search feature by digital feature. She wrote:
 
“The Government’s app-by-app, feature-by-feature method of granting Fourth Amendment protection misapprehends the very nature of modern cell-phone use. Pretty much everything a person does on a smartphone requires some kind of opt-in – an ‘affirmative act’ beyond ‘powering up’ to utilize a given app or service.”
 
Justice Kagan added:
 
“The Government wishes to disconnect all those [private] uses from the mere act of carrying a turned-on cell phone … with only the latter receiving assured Fourth Amendment protection. But that is to imagine that all of us are living in dumb flip-phone days. The point of carrying smartphones is what is on them” (emphasis added).
 
In its conclusion, the Court’s opinion harked back to Carpenter to define the access of historical location information, whether from a cell tower or Google’s Location History, as a search.
 
Monday’s ruling, however, does not fully resolve this case. The Supreme Court is sending the case back to the Fourth Circuit to define the probable cause requirements for every stage of the warrant process and to determine what the proper scope of the search should be.
 
Still, this is a monumental victory for privacy. Until now, as PPSA emphasized in our amicus brief, Carpenter has been treated by law enforcement as a narrow ruling that did not extend beyond location histories extracted from cell towers. Today’s ruling makes it clear that the Supreme Court intends to apply these Fourth Amendment principles across the digital landscape.

The U.S. Supreme Court today declined to hear Wikimedia v. NSA, a lawsuit challenging the mass, secret surveillance of Americans’ online communications.
 
The ACLU had gone to court to challenge a National Security Agency program under the Foreign Intelligence Surveillance Act (FISA), which the agency uses to continuously monitor international and domestic communications across the internet’s main pathways.
 
“In analog terms, it’s as if government agents were opening the international letters passing through a U.S. post office en masse, reading the contents, and then keeping many of those letters in a file for years,” wrote Bob Goodlatte, PPSA Senior Policy Advisor and former Chairman of the House Judiciary Committee, in a recent op-ed.
 
Goodlatte compared this intrusion by the government into American’s emails, web-browsing content, and search engine queries to the “general warrants” of the colonial era that had helped spark the American Revolution.
 
“Worse, the government asserts that this case cannot even be litigated,” said Gene Schaerr, PPSA general counsel. “Under the government’s interpretation of the ‘state secrets’ doctrine, major surveillance programs of the government can never be litigated.
 
“This denial shows all the more reason why Congress needs to step in and use the pending reauthorization of Section 702 – a principal surveillance authority in FISA – to close loopholes the government is exploiting.”

​The Supreme Court will consider whether to hear the Project for Privacy and Surveillance Accountability’s petition in Torcivia v. Suffolk County on Nov. 10.
 
The Second Circuit Court of Appeals ignored the obvious application of a SCOTUS ruling in Caniglia against the police for entering the home of a New York man to confiscate his guns on the basis of the “community caretaking” exception to the Fourth Amendment. The Second Circuit affirmed the right to do the same to another man in New York State on a similar, but more malleable “special needs” doctrine – which is essentially any priority the government deems important.
 
PPSA hopes the Supreme Court grants its petition and takes this opportunity to reinforce the plain meaning of its ruling and the Fourth Amendment.

​In a 6-3 decision today, the U.S. Supreme Court granted U.S. Customs and Border Patrol agents who violate the Fourth Amendment and other provisions of the U.S. Constitution almost total immunity from lawsuits. This ruling shrinks the scope of Bivens v. Six Unknown Agents (1971), in which the Court held that a “violation of [the Fourth Amendment] by a federal agent acting under color of his authority gives rise to a cause of action for damages.”
 
In January, PPSA had filed an amicus brief on behalf of Robert Boule in his quest to obtain justice after being warrantlessly searched and manhandled by Border Patrol Agent Erik Egbert near the Canadian border.

PPSA had noted that since the Magna Carta, the right to sue the Crown for a violation of one’s rights has been a basic principle of English law. Shortly after the American Revolution, U.S. federal courts recognized a common-law right of individuals to sue government officials for damages to remedy violations of foundational law. As English jurist William Blackstone noted, it would be an “absurdity in any system of positive law, to define any possible wrong, without any possible redress.”

Similar logic appears in the sharp, though partial dissent of Justice Sonia Sotomayor, joined by Justices Stephen Breyer and Elena Kagan. She noted the extent to which Bivens has been narrowed. Justice Sotomayor wrote:
 
“Respondent Robert Boule alleges that petitioner Erik Egbert, a U.S. Customs and Border Patrol agent, violated the Fourth Amendment by entering Boule’s property without a warrant and assaulting him. Existing precedent permits Boule to seek compensation for his injuries in federal court …
 
“The Court goes to extraordinary lengths to avoid this result: It rewrites a legal standard it established just five years ago, stretches national-security concerns beyond recognition, and discerns an alternative remedial structure where none exists. The Court’s innovations, taken together, enable it to close the door to Boule’s claim and, presumably, to others that fall squarely within Bivens’ ambit.”
 
Justice Sotomayor was clear that she does not believe that today’s ruling overrules Bivens. But, she wrote, “it nevertheless contravenes precedent and will strip many more individuals who suffer injuries at the hands of other federal officers, and whose circumstances are materially indistinguishable from those in Bivens, of an important remedy.”
PPSA will remain alert to other efforts to curtail Americans’ ability to protect their rights by suing law enforcement officers when they violate the law.