EFF, along with the national ACLU, the ACLU affiliates in Maryland, North Carolina, South Carolina, and Virginia, and the National Association of Criminal Defense Lawyers (NACDL) filed an amicus brief in the U.S. Court of Appeals for the Fourth Circuit urging the court to require a warrant for border searches of electronic devices under the Fourth Amendment, an argument EFF has been making in the courts and Congress for nearly a decade. The Fourth Circuit heard oral arguments on May 8. The Knight Institute at Columbia University and Reporters Committee for Freedom of the Press also filed a helpful brief focusing on the First Amendment implications of border searches of electronic devices.

The case, U.S. v. Belmonte Cardozo, involves a U.S. citizen whose cell phone was manually searched after he arrived at Dulles airport near Washington, D.C., following a trip to Bolivia. He had been on the government’s radar prior to his international trip and had been flagged for secondary inspection. Border officers found child sexual abuse material (CSAM) on his phone, and he was later arrested and criminally charged.

The district court denied the defendant’s motion to suppress the images and other data obtained from the warrantless search of his cell phone. He was ultimately convicted of child pornography and sexual exploitation of minors because he had used social media to entice minors to send him sexually explicit photos of themselves.

The number of warrantless device searches at the border and the significant invasion of privacy they represent is only increasing. In Fiscal Year 2025, U.S. Customs and Border Protection (CBP) conducted 55,318 device searches, both manual (“basic”) and forensic (“advanced”).

A manual search involves a border officer tapping or mousing around a device. A forensic search involves connecting another device to the traveler’s device and using software to extract and analyze the data to create a detailed report the device owner’s activities and communications. However, both search methods are highly privacy-invasive, as border officers can access the same data that can reveal the most personal aspects of our lives, including political affiliations, religious beliefs and practices, sexual and romantic affinities, financial status, health conditions, and family and professional associations.

In our amicus brief, we argued that the Fourth Circuit should adopt the same legal standard for both manual and forensic searches, and that standard should be a warrant supported by probable cause and issued by a neutral judge. The highly personal nature of the information found on electronic devices is why there should not be different legal standards for different methods of search, and why a judge should determine whether the government has provided credible preliminary evidence that there’s a likelihood that further evidence will be found on the device indicating wrongdoing by the specific traveler.

Moreover, we argued that “the process of getting a warrant is not unduly burdensome,” and that “getting a warrant would not impede the efficient processing of travelers. If border officers have probable cause to search a device, they may retain it and let the traveler continue on their way, then get a search warrant. Or, where there is truly no time to go to a judge, the exigent circumstances exception may apply on a case-by-case basis.”

The Fourth Circuit in prior cases only considered forensic device searches at the border. In U.S. v. Kolsuz (2018), the court held that the forensic search of the defendant’s cell phone at the border “must be considered a nonroutine border search, requiring some measure of individualized suspicion” of a transnational offense, but the court declined to decide whether the standard is only reasonable suspicion or instead a probable cause warrant. Then in U.S. v. Aigbekaen (2019), the court held that a forensic device search at the border in support of a purely domestic law enforcement investigation requires a warrant. The court also reiterated the general Kolsuz rule for a forensic border-related device search: the “Government must have individualized suspicion of an offense that bears some nexus to the border search exception's purposes of protecting national security, collecting duties, blocking the entry of unwanted persons, or disrupting efforts to export or import contraband.” Now, manual searches are before the court.

In urging the Fourth Circuit to adopt a warrant standard for both manual and forensic device searches at the border, we argued that the U.S. Supreme Court’s balancing test in Riley v. California (2014) should govern the analysis here. In that case, the Court weighed the government’s interests in warrantless and suspicionless access to cell phone data following an arrest, against an arrestee’s privacy interests in the depth and breadth of personal information stored on a cell phone. The Court concluded that the search-incident-to-arrest warrant exception does not apply, and that police need to get a warrant to search an arrestee’s phone.

The U.S. Supreme Court has recognized for a century a border search exception to the Fourth Amendment’s warrant requirement, allowing not only warrantless but also often suspicionless “routine” searches of luggage, vehicles, and other items crossing the border. The primary justification for the border search exception has been to find—in the items being searched—goods smuggled to avoid paying duties (i.e., taxes) and contraband such as drugs, weapons, and other prohibited items, thereby blocking their entry into the country.

But a traveler’s privacy interests in their suitcase and its contents are minimal compared to those in all the personal data on the person’s cell phone or laptop. And a travelers’ privacy interests in their electronic devices are at least the same as those considered in Riley. Modern devices, over a decade later, contain even more data that can reveal even more intimate details about our lives.

We hope that the Fourth Circuit will rise to the occasion and be the first circuit to fully protect travelers’ Fourth Amendment rights at the border.