No Suspicion Required: Second Circuit Permits Warrantless Manual Cellphone Searches at the Border

On September 17, 2026, the U.S. Court of Appeals for the Second Circuit held that no suspicion is required before the government manually searches a traveler’s cellphone at the border in United States v. Alisigwe.[1] The decision resolves a split among district courts within the circuit and aligns the Second Circuit with other circuits that have addressed suspicionless manual cellphone searches at the border.[2] The ruling has significant implications for government investigations, particularly those involving international travel and cross border conduct. It also gives investigators another potential avenue for obtaining evidence stored on electronic devices.

Background

Between 2017 and 2020, Chinwendu Alisigwe, a U.S. lawful permanent resident, opened 36 bank accounts using fraudulent passports and driver’s licenses. He used these accounts to deposit millions of dollars from other fraudulent schemes, transfer money between them to disguise the nature of the proceeds, and wire portions of the stolen funds to accounts in China and the United Kingdom.

Officers from Homeland Security Investigations (“HSI”) and Customs and Border Protection (“CBP”) stopped Alisigwe at John F. Kennedy International Airport in 2019 and 2021, and on both occasions asked him to unlock his cellphone. Officers scrolled through the device and photographed evidence of the fraud scheme, including images of stolen personally identifiable information and a WhatsApp message to a co-conspirator.

Alisigwe was subsequently arrested and charged with conspiracy to commit bank fraud, bank fraud, aggravated identity theft, and conspiracy to commit money laundering. He moved to suppress the cellphone evidence, arguing that the Fourth Amendment required a warrant before officers searched his phone. The district court denied the motion, concluding that cellphone searches at the border require reasonable suspicion but that the government had met that standard. The district court also noted that even if a warrant were required, the good faith exception would apply because “neither the Supreme Court nor the Second Circuit has addressed the lawfulness of warrantless searches of cellphones at the border.” Following trial, Alisigwe was convicted of all counts except aggravated identity theft and sentenced to five years of imprisonment.

The Second Circuit’s Alisigwe Decision

The Second Circuit affirmed, but on broader grounds than the district court. The court held that no suspicion—not even reasonable suspicion—is required for a manual search of a traveler’s cellphone at the border.

The court’s reasoning followed from Fourth Amendment precedent distinguishing between “routine” and “non-routine” border searches. Routine searches—such as inspections of luggage, clothing, wallets, and vehicles—do not require any individualized suspicion of criminal activity. Non-routine searches—such as strip searches and body cavity searches—involve a significantly greater intrusion into personal privacy and require at least reasonable suspicion that the traveler is engaged in criminal conduct. The critical question in Alisigwe was whether the search of a cellphone should be classified as routine or non-routine given the vast amount of personal information modern devices contain.

The majority concluded that manual cellphone searches are routine border searches. Because the search is of property rather than of a person, the court treated it as categorically routine, regardless of the data contained on it. The court rejected the argument that the U.S. Supreme Court’s decision in Riley v. California,[3] which required a warrant for cellphone searches incident to arrest, compelled a different result. Riley addressed the search incident to arrest exception, the rationales for which—preventing harm to officers and destruction of evidence—apply differently to digital data. The border search exception rests on a broader foundation: the government’s sovereign interest in “preventing the entry of unwanted persons and effects.” Because that interest applies with equal force to digital data, Riley did not control the border search analysis.

The court emphasized that “cell phones can contain the contraband the border search doctrine means to intercept” and that the stolen personal information on Alisigwe’s phone was “contraband whether in digital or physical form.” The court also reaffirmed that border searches may be pretextual and rejected an argument raised by amici that the First Amendment imposes an independent warrant requirement for cellphone searches at the border.

Judge Lee concurred in the judgment but wrote separately to challenge the majority’s routine/non-routine analysis. While agreeing that neither a warrant nor probable cause is required, she argued that manual cellphone searches are sufficiently intrusive to qualify as non-routine and therefore should require at least reasonable suspicion. Labeling a cellphone as “property” and therefore dispensing with any suspicion requirement, she wrote, “denies a fundamental reality of the modern cellphone—it is not a suitcase.” A cellphone search can expose medical records, financial information, personal messages, browsing habits, and location tracking—a level of intrusion “much closer . . . to a strip search than it is to the search of luggage.” She urged the court to be “wary of converting” the border search exception into “a categorical rule that renders every search of every cellphone at the border ‘routine.’”

The Remaining Circuit Split: Forensic Searches

Alisigwe aligns the Second Circuit with the other circuits that have considered manual cellphone searches at the border, but leaves unresolved a separate circuit split over forensic searches. The Eleventh Circuit has held that even forensic searches require no suspicion.[4]  By contrast, the Fourth and Ninth Circuits have required at least reasonable suspicion.[5] Although the court expressly declined to address forensic searches, aspects of the majority’s reasoning—including its categorical treatment of cellphones as property—may bear on that question in a future case.

That question sits at the intersection of the Supreme Court’s permissive border search cases and its more recent decisions recognizing the unique privacy interests in digital data. The Court has never addressed the border search exception’s application to electronic devices. And Judge Lee’s concurrence—arguing that the majority’s approach “eliminates Fourth Amendment protections” for cellphone data at the border—identifies arguments likely to be pressed in future cases.

Implications for Practice

• Manual border cellphone searches require no suspicion. Cellphones often contain evidence in government investigations—communications with alleged co-conspirators, banking and financial records, and contemporaneous documents bearing on intent. And because manual border searches require no individualized suspicion and may be conducted for investigative purposes beyond ordinary customs and immigration enforcement, federal agencies may use border encounters to further criminal investigations even when the investigation itself is unrelated to immigration, customs enforcement, or national security. Individuals who are subjects of, or even tangentially related to, investigations should understand that their electronic devices may be searched at the border without any individualized suspicion, and that evidence obtained may be used in a subsequent prosecution, not only one related to border enforcement.
• Data management practices are critical. Individuals who travel internationally and who could be subjects of, or even tangentially related to, investigations could face suspicionless manual cellphone searches upon entering the United States, making appropriate management of the amount of data carried during international travel critical.
• Open questions: passcodes and forensic searches. One notable feature of Alisigwe is what it does not On both occasions, Alisigwe unlocked his cellphone. The court therefore had no occasion to address whether the government can compel a traveler to provide a passcode or biometric authentication or whether such compulsion implicates the Fifth Amendment. Courts have divided on whether compelled decryption constitutes “testimonial” communication, and the Second Circuit has not resolved the question. Even after Alisigwe, therefore, distinct constitutional questions may arise when the government seeks to compel a traveler to unlock a device rather than the traveler providing access voluntarily.

Furthermore, because the standard for forensic searches remains unresolved, defense counsel should seek discovery as to the precise nature and scope of any search, including whether the search went beyond a manual review. Such evidence may support a suppression motion, though the Second Circuit’s reasoning in Alisigwe will likely inform the analysis if the court is asked to address forensic searches in a future case.

[1] United States v. Alisigwe, No. 24-960 (2d Cir. Sept. 17, 2026).

[2] Alasaad v. Mayorkas, 988 F.3d 8, 17 (1st Cir. 2021); United States v. Belmonte Cardozo, 181 F.4th 461, 471 (4th Cir. 2026); United States v. Molina-Isidoro, 884 F.3d 287, 292 (5th Cir. 2018); United States v. Mendez, 103 F.4th 1303, 1309 (7th Cir. 2024); United States v. Xiang, 67 F.4th 895, 900 (8th Cir. 2023); United States v. Cano, 934 F.3d 1002, 1016 (9th Cir. 2019); United States v. Vergara, 884 F.3d 1309, 1312–13 (11th Cir. 2018).

[3] 573 U.S. 373 (2014).

[4] See United States v. Pulido, 133 F.4th 1256, 1275 (11th Cir. 2025).

[5] See United States v. Kolsuz, 890 F.3d 133, 146 (4th Cir. 2018); see also United States v. Cotterman, 709 F.3d 952, 967 (9th Cir. 2013).

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