In December 2024, Judge LaShann DeArcy Hall of the U.S. District Court for the Eastern District of New York issued an opinion ruling that searches for U.S. persons in databases containing information previously collected under Section 702 of the Foreign Intelligence Surveillance Act (FISA) are protected by the Fourth Amendment and must be performed pursuant to a warrant or an exception to the warrant requirement. The ruling, a declassified version of which was released on Jan. 21, 2025, marks the first time that a court has ruled these searches (known as “U.S. person queries” or “backdoor searches”) are subject to a warrant requirement. While it is unclear how significant or long-lasting a precedent the ruling will prove to be, it will likely have a significant operational impact and could shift the debate over the propriety of a statutory warrant requirement when Congress considers whether and in what form to reauthorize Section 702 in April 2026.
The Debate on a U.S. Person Warrant Requirement for FISA Section 702
Section 702 of FISA authorizes targeting of non-U.S. persons (individuals who are not U.S. citizens or lawful permanent residents, and companies based outside of the United States) outside the United States under procedures approved by the Foreign Intelligence Surveillance Court (FISC). It does not require probable cause or case-by-case judicial orders. Section 702 surveillance of a non-U.S. person overseas may “incidentally” collect communications that U.S. persons or persons within the United States, who are subject to Fourth Amendment search and seizure protections, have with the target.
To safeguard the privacy of U.S. persons whose communications are incidentally obtained, Congress required that information collected under Section 702 be subject to minimization procedures and, more recently, querying procedures. These procedures apply when analysts or law enforcement officers “query” a database containing information collected under Section 702 using a U.S. person’s identifier. The minimization and query procedures are intended to protect the non-target U.S. communicants, consistent with the need of the United States to obtain, analyze, and disseminate foreign intelligence information.
The question of whether U.S. person queries should be considered a “search” at all for Fourth Amendment purposes, and in turn whether they should require a warrant as a constitutional or prudential matter, has split both major political parties. Section 702 periodically sunsets and has to be reauthorized, and the last round of reauthorization found unlikely allies such as Senators Ron Wyden (D-OR) and Mike Lee (R-UT) co-sponsoring legislation that would have imposed a statutory warrant requirement. The requirement was not incorporated into the final reauthorization bill, but the last-minute renewal of Section 702 came with a much shorter sunset than prior authorizations. This shorter period likely reflects increasing diversity of opinion on both sides of the aisle regarding the warrant requirement and other FISA questions, and a desire to revisit those issues soon without letting the authority lapse.
It is not clear what position the Trump administration will take. President Donald Trump himself urged Congress to “kill FISA” during the previous round of re-authorization. (When he signed the 2018 re-authorization into law, President Trump declared that he “would have preferred a permanent reauthorization of Title VII [which includes Section 702] to protect the safety and security of the Nation.”)
President Trump’s Central Intelligence Agency (CIA) Director, former Director of National Intelligence (DNI) John Ratcliffe, expressed unqualified opposition to a warrant requirement because it would introduce “unreasonable delays” in national security investigations and, during his testimony before the Senate Select Committee on Intelligence, stated that a warrant requirement would create the “danger” that “you really don’t have the information to obtain a warrant.” (see video starting at 01:58:50). In other words, Ratcliffe, who is also a former United States Attorney, does not believe that probable cause should be necessary to predicate a U.S. person query of Section 702 information. Senator John Cornyn (R-TX) expressed his agreement during the hearing and even encouraged Ratcliffe to share his analysis with President Trump’s nominees for other national security positions (see video at 02:01:25).
On the other hand, in response to questioning by Sen. Lee during her confirmation proceeding before the Senate Judiciary Committee, Pamela Bondi, President Trump’s nominee for Attorney General, agreed with Sen. Lee that U.S. person queries should not be conducted “without some kind of probable cause showing.” (see video at 01:47:52). Ms. Bondi’s response came after Sen. Lee restated his endorsement of a warrant requirement, but Ms. Bondi herself did not substantively address the warrant requirement in particular.
With confirmation proceedings for President Trump’s nominees for DNI and Federal Bureau of Investigation (FBI) Director scheduled in the next few days, where the nominees fall on the spectrum between Senators Lee and Cornyn may reveal the new administration’s view of a warrant requirement. With Judge Hall’s decision in Hasbajrami, these political debates will take place against a shifting legal background.
Earlier Hasbajrami litigation
In 2012, Agron Hasbajrami, a United States person, pled guilty in the Eastern District of New York to attempting to provide material support to terrorists and was subsequently sentenced to 180 months in prison. While Hasbajrami was in prison, prosecutors disclosed that some evidence it would have introduced against Hasbajrami was acquired through FISA orders that were predicated upon information the government collected pursuant to Section 702 and that investigators later retrieved in response to queries of previously collected information. Hasbajrami was allowed to withdraw his guilty plea. He moved to suppress evidence acquired directly through Section 702 and evidence acquired through means predicated on such information, such as “traditional” FISA orders that relied upon it. The district court denied Hasbajrami’s motion and he pled guilty while reserving his right to appeal.
On appeal, the Second Circuit identified three issues: whether the Fourth Amendment permitted (1) “incidental collection,” or the collection of (non-targeted) U.S. persons’ communications with Section 702 targets; (2) “inadvertent collection,” or collection resulting from the targeting of an individual mistakenly believed to be a non-U.S. person outside the United States; and (3) queries of databases containing information previously collected under Section 702.
The court found that incidental collection does not violate the Fourth Amendment and that it was unnecessary to address inadvertent collection. The court also found that, under some circumstances, queries “could violate the Fourth Amendment” if they were unreasonable. The court based that conclusion on three premises:
- The court relied on the U.S. Supreme Court’s 2014 decision in Riley v. California as well as cases involving searches that extended beyond their initial justification to distinguish law enforcement’s lawful possession of material from its search of that material, whether that material is a cell phone, digital media, or a suitcase. The court cataloged cases in which law enforcement requires additional authority to search objects or information it lawfully possesses.
- The court recognized the “sweeping . . . technological capacity” and broad scope of Section 702 collection and expressed concern that the intelligence collection program collected a vast amount of communications to be stored and later searched. Building on the Supreme Court’s increasing recognition of the impact of technology on Fourth Amendment doctrines, the court likened Section 702 to a “dragnet” collecting information that could be subject to a “general warrant” in the form of subsequent queries.
- The court acknowledged that Section 702 prohibits targeting a non-U.S. person outside the United States as a means to collect information about a U.S. person or person within the United States, but found that “[t]reating querying as a Fourth Amendment event” provided a backstop to ensure that such targeting did not occur.
Although the court did not specifically state that querying previously collected information constituted a search for Fourth Amendment purposes, it remanded the case to the district court for further factual findings and analysis of whether “whatever was done was consistent with the Fourth Amendment.”
Judge Hall’s ruling
On remand, consistent with the Second Circuit’s findings, Judge Hall started from the premise that “simply acquiring Defendant’s communications under Section 702, albeit lawfully, did not, in and of itself, permit the government to later query the retained information.” Although the Second Circuit did not conclude that a warrant was required, Judge Hall interpreted the mandate to conduct a Fourth Amendment assessment to indicate that queries constituted Fourth Amendment searches. And Judge Hall cited “the legion of case law holding that a warrant is presumptively required for law enforcement to conduct a search.”
Imposing the warrant requirement did not end the inquiry, because the Fourth Amendment allows exceptions to the warrant requirement for searches and seizures under certain conditions. Among other exceptions to the warrant requirement, the government can lawfully conduct a search without a warrant under the “foreign intelligence” exception to the warrant requirement. Judge Hall found that there was “no legitimate debate” that protecting national security goes beyond “garden-variety law enforcement,” so the government met the first predicate of the exception. But to satisfy the foreign intelligence exception, the government must also establish that having to obtain a warrant would frustrate its legitimate enforcement needs. Judge Hall found that under the specific facts of the case, the government could not meet that burden. Although the factual details are heavily redacted, it appears that the timeframe of the queries conducted in the case, which took place over a period of at least seven months, did not reflect the exigency required to satisfy this second prong.
Judge Hall did not conclude that warrants are always required to query information previously collected under Section 702 for U.S. person information. But Judge Hall sharply distinguished the initial collection of information from subsequent searches of that information and applied separate Fourth Amendment analyses to each step. As a result, under Judge Hall’s rule, U.S. person queries of Section 702 information are searches, and therefore require either a warrant or an exception.
By its own terms and in the context of Riley, Carpenter v. United States, and other recent decisions that surprised law enforcement by “updating” Fourth Amendment jurisprudence to track technological advancement, Hasbajrami emphasizes the substantial intrusion into privacy involved in accessing an individual’s electronic data, particularly when that data is collected without the individual’s participation or knowledge, can be collected and stored in large quantities, and can be searched with minimal effort. Under Judge Hall’s rule, to conduct warrantless U.S. person searches of such data consistent with the Fourth Amendment, the government must demonstrate its need to conduct the search without delay.
What comes next?
Judge Hall’s ruling vindicates the politicians, scholars, and advocates who have long argued that U.S. person queries require a warrant not just as sound policy, but as a matter of law. Judge Hall denied Hasbajrami’s motion to suppress based on the United States v. Leon exception to the Fourth Amendment exclusionary rule. As a result, Hasbajrami will almost certainly appeal the decision. (At time of writing, he has not filed a notice of appeal.) If the Second Circuit affirms the core of Judge Hall’s ruling—that U.S. person queries of Section 702 information require a warrant and that the foreign intelligence exception did not excuse that requirement in this case—the split between that court and the FISC would deepen (the FISC has held that U.S. person queries are not a distinct Fourth Amendment event that must independently be reasonable). But while the decision is important, several factors are likely to blunt its significance to criminal litigation in practice.
First, the opinion (like many Fourth Amendment decisions) is highly fact-dependent. While Judge Hall’s ruling that “simply acquiring [Hasbajrami’s] communications under Section 702, albeit lawfully, did not in and of itself, permit the government to later query the retained information” was sweeping, she left open the possibility that warrantless queries could be justified by the foreign intelligence exception. Judge Hall did not narrow the scope of the foreign intelligence exception, but rather made clear that her ruling was based “on the record of this case,” including a timeframe for the searches that undercut any suggestion that obtaining a warrant would have unduly slowed down the investigation.
Relatedly, the queries in question all took place in 2011, long before FBI employees were required by law and policy to keep detailed records of the queries they performed and the reasons for them. As Judge Hall noted in her decision, the “incomplete record” the government furnished regarding these queries prevented it from carrying its burden of proving that its searches were reasonable. But for any prosecutions that rely on evidence obtained or derived from U.S. person queries performed since the FBI began keeping records in 2020, the government should be able to furnish the court with more fulsome information, which may help it establish why obtaining a warrant would have been operationally unfeasible. And similar to cases that were decided after Carpenter in which law enforcement obtained location information without search warrants, even courts that apply the Fourth Amendment to U.S. person queries may make allowances for queries conducted before the rule was announced.
Next, the opinion may be of limited precedential value because so much of it is redacted. The specifics of how the FBI used U.S. person queries in its investigation of Hasbajrami remain classified. This will hinder attorneys in other cases seeking to challenge the constitutionality of U.S. person queries because it will limit their ability to compare the facts and circumstances of those searches with the specifics of the queries at issue in Hasbajrami–though simply having a case saying that U.S. person queries require a warrant or an exception to the warrant requirement is significant.
Finally, Judge Hall’s ruling will almost certainly have no impact on the FISC’s annual review of the government’s Section 702 certifications and procedures. The FISC has repeatedly declined to adopt the Second Circuit’s view that the acquisition and querying of Section 702 information are distinct Fourth Amendment events that each must be independently reasonable. Nor has it ever found that U.S. person queries require a warrant to be consistent with the Fourth Amendment. Accordingly, there is virtually no chance that, based on Judge Hall’s opinion, the FISC will require that U.S. person queries be performed pursuant to a warrant.
On the other hand, Hasbajrami could have a substantial operational impact. Other courts may adopt Judge Hall’s reasoning and may similarly interpret the Second Circuit’s opinion to find that a U.S. person query is a search under the Fourth Amendment. No agent, no prosecutor, and no victim would want to learn that a court considers a warrant necessary for a U.S. person query only once a case reaches a suppression hearing or after a conviction is challenged on appeal. National security prosecutors have every reason to avoid unnecessary, self-inflicted risk. So the government could decide to impose Judge Hall’s rule in at least some cases to avoid downstream suppression risk. To be sure, to many that may be a desired outcome, but commentators such as ex-Deputy Director of the FBI Andy McCabe have argued that querying previously collected information is an important step at the beginning of a national security investigation into a U.S. person, often before probable cause can be established.
And even if the impact of Hasbajrami is limited to the Second Circuit, the New York district courts handle a heavy percentage of U.S. national security prosecutions. Adding procedural risk to national security prosecutions in the Second Circuit can have a substantial effect on national security prosecutors–just ask any prosecutor who has raised a Classified Information Procedures Act claim in a jurisdiction that applies the Second Circuit’s decision in United States v. Aref (requiring head-of-department declarations).
Nor is the outcome certain on appeal at the Second Circuit. While that court held previously that U.S. person queries “have important Fourth Amendment implications,” it did not expressly find a warrant requirement in Hasbajrami and left open the possibility that such searches could be constitutionally reasonable without a warrant. The querying procedures that Section 702 now requires and that the FISC approves may provide a basis for the Second Circuit to find searches reasonable without a warrant. And given the significant deference the courts grant the executive regarding matters of national security, it may well decide that the government’s interests in performing warrantless U.S. person queries outweigh the harms to Americans’ privacy.
Of course, one critical variable is the position the Department of Justice (DOJ) takes on appeal. Under prior administrations, it would have been safe to predict that DOJ would defend a terrorism conviction and would defend the constitutionality of queries under Section 702. The Trump administration’s position, however, is not yet clear. Some Republicans support a warrant requirement and some do not. President Trump’s CIA Director opposes the requirement, but his Attorney General nominee appears to support it. To be sure, DOJ could argue that the Fourth Amendment does not require a warrant for U.S. person queries, even while the Trump administration considers or advocates a warrant requirement based on a non-Constitutional statutory argument (much like FISA and the Electronic Communications Privacy Act when they were first enacted).
The opinion will likely also be viewed as significant in the halls of Congress, which must decide by April 2026 whether and in what form to reauthorize Section 702. During the last round of reauthorization, an amendment requiring a warrant for U.S. person queries failed in the House by a tie vote (A modified version of the amendment was voted down in the Senate by a wider margin). A key theme in the resistance to the warrant requirement, both inside and outside of Congress, was that no court to reach the merits of the issue had ever ruled that warrantless U.S. person queries violated the Fourth Amendment. Now that is no longer the case, members will face more pressure to impose a warrant requirement by statute.
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Judge Hall’s Hasbajrami decision marks the first time a court has ruled that U.S. person queries must be performed pursuant to a warrant or an exception to the warrant requirement to satisfy the Fourth Amendment. While it remains to be seen how impactful the opinion will be in future litigation regarding the constitutionality of warrantless U.S. person queries, it will significantly influence the executive branch’s use of Section 702 evidence in national security investigations and prosecutions and will inform congressional debates regarding the propriety and necessity of a statutory warrant requirement. As Congress decides whether and in what form to reauthorize Section 702 when it expires next year, expect to hear the name “Hasbajrami” repeatedly.
(Editor’s Note: Readers may also be interested in Just Security’s series on the FISA Section 702 reauthorization and reform debate.)