In December, a federal court in Brooklyn became the first to hold that searches of information acquired under Section 702 of the Foreign Intelligence Surveillance Act (FISA) for U.S. persons’ communications are subject to the Fourth Amendment’s warrant requirement. The ruling, which was declassified in January, was a win for privacy advocates who have long argued as much. But the decision also previews a Fourth Amendment hurdle that awaits beyond the warrant requirement: the foreign intelligence exception, under which courts have upheld warrantless searches to obtain foreign intelligence in certain circumstances. If embraced by other courts or on appeal, the decision’s expansive articulation of this exception could swallow the new rule, undermining the impact of applying the warrant requirement to these searches in the first place.
Section 702 of the Foreign Intelligence Surveillance Act
Section 702 of FISA authorizes the government to collect the electronic communications of foreigners located abroad without a warrant. The government acquires hundreds of millions of these communications annually—phone calls, emails, text messages, and so on—excused from the Fourth Amendment’s warrant requirement upon certification by the Attorney General and the Director of National Intelligence that the surveillance does not target U.S. persons (as used here, American citizens and legal permanent residents). But because Americans regularly communicate with foreigners located abroad, 702 surveillance inevitably sweeps in Americans’ private phone calls, emails, and text messages—information that the government would normally need a warrant to collect.
The central premise of Section 702’s warrantless surveillance is that it targets foreigners located abroad and not Americans. And yet, once the government has collected data under Section 702, the statute—as amended in 2018 and 2024—permits the government to search that data for Americans’ communications without a warrant in almost all cases. For years, privacy advocates have criticized these warrantless searches, known as “U.S. person queries” or “backdoor searches,” on the ground that they violate the Fourth Amendment. In her December decision, Judge LaShann DeArcy Hall of the U.S. District Court for the Eastern District of New York agreed—at least with regard to the searches in that case.
The Hasbajrami Case
In 2011, Agron Hasbajrami, a legal permanent resident in the United States, was arrested and charged with providing material support to a terrorist organization. Hasbajrami first pleaded guilty to the charges, but when prosecutors disclosed that some of the evidence against him was derived from warrantless Section 702 collection, he withdrew his guilty plea and sought to suppress the evidence obtained from backdoor searches, as well as any evidence obtained as a result of that evidence (the “fruit of the poisonous tree”). The district court denied Hasbajrami’s motion to suppress on the basis that collection of communications under 702 comports with the Fourth Amendment, but without addressing the specifics of any querying of 702-acquired information for Hasbajrami’s communications.
On appeal, the Second Circuit held that queries of 702-acquired information are separate Fourth Amendment events from the initial collection and must independently comport with the Fourth Amendment. The Second Circuit remanded to the district court to determine whether any queries in the case violated the Fourth Amendment. On remand, the district court held that U.S. person queries are searches subject to the Fourth Amendment’s warrant requirement, under which the government must either obtain a warrant or show that the search falls within an exception to the warrant requirement.
As others have noted, this ruling was significant: it marked the first time a court has held that U.S. person queries are subject to the warrant requirement. The specialized court created by FISA that reviews the government’s surveillance procedures under 702—the Foreign Intelligence Surveillance Court (FISC)—has concluded that U.S. person queries are not separate Fourth Amendment events from initial 702 collection and, therefore, no warrant is required to conduct them. A small handful of non-FISA courts have agreed or found ways to avoid the question. The Hasbajrami court dealt with the question directly and became the first court to hold that the warrant requirement applies to U.S. person queries.
But the ruling’s import does not end there. As the first court to apply the warrant requirement to U.S. person queries, it also became the first court to directly confront whether U.S. person queries fall within the foreign intelligence exception to the warrant requirement. It is this portion of the court’s decision that should give privacy advocates pause.
What is the foreign intelligence exception?
The Fourth Amendment protects “[t]he right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures.” Under Supreme Court jurisprudence, warrantless searches are per se unreasonable unless they fall within certain carefully delineated exceptions. In 1972, the Supreme Court declined to recognize an exception to the warrant requirement for surveillance of domestic organizations for national security purposes. The Court explicitly left open the question of whether the warrant requirement would apply if the government were seeking intelligence about a foreign power or its agents.
In a series of circuit court cases that followed, several circuits decided the question left open by the Supreme Court and recognized a “foreign intelligence exception” to the warrant requirement. Recognizing that the exception “must be carefully limited,” the Fourth Circuit, in United States v. Truong, limited the exception to circumstances in which (1) the object of the search or the surveillance is a foreign power, its agent or collaborators and (2) the search or surveillance is conducted primarily for foreign intelligence purposes. Other courts applied a similar analysis. The Third Circuit went further, emphasizing the importance of post-search judicial review as an additional safeguard.
These careful limitations did not last. Decisions by the FISC and the Foreign Intelligence Surveillance Court of Review (FISCR), the appellate court established to review FISC opinions, have abandoned the criteria set forth in Truong and recognized a much more expansive foreign intelligence exception, as explained in a 2015 Brennan Center report. The FISCR has analogized the foreign intelligence exception to the Supreme Court’s “special needs” decisions, in which the Court has excused the traditional warrant requirement where the government has a “special need” other than law enforcement that could not be met if an ordinary probable cause warrant were required. (The “special needs” doctrine originated in a 1967 case authorizing municipal health inspectors to search for fire hazards in homes and businesses without obtaining a warrant based on probable cause of criminal activity.)
In 2008, reasoning that foreign intelligence collection is a “special need” that is fundamentally different from ordinary criminal law enforcement and that obtaining a warrant would impede time-sensitive acquisitions, the FISCR dispensed with the warrant requirement specifically for surveillance that “is conducted to obtain foreign intelligence for national security purposes and is directed against foreign powers or agents of foreign powers reasonably believed to be located outside the United States.” In the years since, the FISA Courts have extended the exception to cover warrantless surveillance of persons within the United States who are agents of a foreign power, and foreigners located abroad who are not agents of a foreign power. The FISA Courts also explicitly rejected Truong’s requirement that foreign intelligence collection must be the “primary purpose” of surveillance to qualify for the exception, on the ground that criminal investigations and foreign intelligence objectives are often “interrelated.”
The FISA Courts’ analysis is problematic in multiple respects. For one thing, in concluding that a warrant requirement might impede time-sensitive intelligence collection, the FISA Courts largely ignored the fact that this may also be the case in criminal investigations—and that courts have addressed this problem by recognizing an “exigency” exception. Moreover, as the Brennan Center’s 2015 report noted, the FISA Courts’ analysis of the relationship between foreign intelligence and criminal investigations attempts to have it both ways:
On the one hand, the [FISCR] characterized foreign intelligence investigations as fundamentally different from ordinary criminal investigations, to the point that the former may be labeled a “special need” and placed in an entirely separate category for Fourth Amendment purposes. On the other hand, the court found criminal proceedings to be such a fundamental and inextricable element of foreign intelligence investigations as to render the “primary purpose” test arbitrary and unworkable. These premises are, at a minimum, in tension.
The result of this flawed analysis is an exception that blurs the line between searches for foreign intelligence collection and ordinary law enforcement purposes.
The Supreme Court has never ruled on the foreign intelligence exception, and only a few courts outside of the FISA Courts have considered it in recent decades. Moreover, no court has been directly faced with the question of whether the foreign intelligence exception applies to U.S. person queries of communications acquired under Section 702. The Hasbajrami court was therefore poised to break new ground.
The Foreign Intelligence Exception in Hasbajrami
Rather than challenging the FISA Courts’ expanded foreign intelligence exception, the district court in Hasbajrami adopted it without question, collapsing the foreign intelligence exception with the special needs doctrine. The court articulated two requirements to satisfy the foreign intelligence exception: the government must show (1) “that the querying of Section 702-acquired information goes beyond garden variety law enforcement” and (2) “that its aims would have been hindered by adhering to the warrant requirement.” Nowhere in this articulation did the court use the words “primary purpose” or “agent of a foreign power.”
Indeed, the Hasbajrami court may have gone further than the FISA Courts. For all their expansions of the foreign intelligence exception, the FISA Courts have never extended it to searches of U.S. persons who are not acting as agents of a foreign power. Hasbajrami, as a legal permanent resident, was a U.S. person, and yet the court did not explicitly find that he was acting as an agent of a foreign power (at least in the declassified portions of the opinion). Nor did the court state that such a finding was required for U.S. person queries to fall within the foreign intelligence exception. Of course, it may have been obvious to the court based on the heavily redacted facts that Hasbajrami was, indeed, acting as an agent of a foreign power. But in failing to discuss it explicitly or articulate it as a requirement, the declassified opinion, at the very least, creates doubt as to whether the foreign intelligence exception’s application to searches of U.S. persons is limited to searches of those acting as agents of foreign powers.
The limitations the court did apply provide little comfort. As noted, the court required the government to show (1) “that the querying of Section 702-acquired information goes beyond garden variety law enforcement” and (2) “that its aims would have been hindered by adhering to the warrant requirement.” The court’s analysis of the first requirement is limited to a single sentence:
Indeed, there can be no legitimate debate that the protection of national security interests involved with foreign intelligence, as it pertains to both the surveillance and querying of 702-acquired information, serve purposes that go beyond garden-variety law enforcement.
The court did not provide any justification for its conclusion that U.S. person queries serve to “protect national security interests involved with foreign intelligence” in general, nor conduct any individualized analysis of the U.S. person queries conducted in Hasbajrami’s case.
Had the court engaged in a more specific analysis, it would have been forced to face the same tension that characterizes the FISA Courts’ reasoning. Although Congress recently prohibited U.S. person queries conducted solely for the purpose of seeking evidence of a crime, FBI querying procedures still authorize queries of 702 data in mixed-motive cases—including those where the primary purpose is to further a criminal investigation. It is highly unlikely that the foreign intelligence component of such investigations can be neatly distinguished from the criminal component. Moreover, allowing warrantless queries in any situation where the government can posit even the slightest foreign intelligence benefit could sideline the Fourth Amendment’s warrant requirement in a significant proportion of criminal cases. That risk is heightened by FISA’s extremely broad definition of “foreign intelligence,” which is not limited to information about foreign threats to the United States, but encompasses information about foreign affairs in general.
The Hasbajrami court also failed to conduct any analysis of whether the particular queries conducted in that case served purposes beyond garden-variety law enforcement. Indeed, such an analysis would have been difficult given the court’s acknowledgement that for at least one of the queries, the government provided no explanation of its purpose. Instead, in a single sentence, the court summarily concluded that queries of 702-acquired information in general “go[] beyond garden variety law enforcement.” To be sure, at the very end of its Fourth Amendment analysis, the court included a caveat in a footnote that its ruling was limited to the facts of the case. But in determining that Section 702 queries go beyond garden-variety law enforcement, the court did not actually engage with those facts.
What could all of this mean in practice? If U.S. person queries categorically serve the government’s “special need” for foreign intelligence and the foreign intelligence exception can apply to searches of U.S. persons regardless of whether they are agents of a foreign power, the foreign intelligence exception as applied to U.S. person queries is reduced to a single requirement: that the government’s “aims would have been hindered by adhering to the warrant requirement.” This is a dangerously low bar given that obtaining a warrant is always, to some extent, an added burden on the government. The government failed to clear that low bar in Hasbajrami only because it failed to put forth any argument as to how its aims would have been hindered by obtaining a warrant. The government can easily remedy that in future cases.
There is much to be celebrated in the Hasbajrami decision—in particular, its holding that U.S. person queries of 702 data are subject to the warrant requirement. But that ruling would lose much of its force if the foreign intelligence exception were permitted to swallow the rule. The Hasbajrami decision’s expansive treatment of the foreign intelligence exception threatens such a result and should be rejected by the Second Circuit if raised on appeal as well as by other courts in future cases.