Searches and Seizures at the Border and the Fourth Amendment Updated March 30, 2021 Congressional Research Service https://crsreports.congress.gov R46601 SUMMARY R46601 Searches and Seizures at the Border and the March 30, 2021 Fourth Amendment Hillel R. Smith Congress has broad authority to regulate persons or items entering the United States, an authority Legislative Attorney that is rooted in its power to regulate foreign commerce and to protect the integrity of the nation’s borders. Exercising this authority, Congress has established a comprehensive framework that Kelsey Y. Santamaria authorizes federal law enforcement officers to inspect and search persons and property at the Legislative Attorney border to ensure that their entry conforms with governing laws, including those relating to customs and immigration. While federal statutes confer substantial authority to conduct border searches, this authority is not absolute. The Fourth Amendment to the U.S. Constitution forbids unreasonable government searches and seizures of “the people,” and this limitation extends to searches conducted at the border. The touchstone of the Fourth Amendment is the reasonableness of a search. The Supreme Court has recognized that searches at the border are “qualitatively different” from those occurring in the interior of the United States, because persons entering the country have less robust expectations of privacy, given the federal government’s broad power to safeguard the nation by examining persons seeking to enter its territory. While law enforcement searches and seizures within the interior of the United States typically require a judicial warrant supported by probable cause, federal officers may conduct routine inspections and searches of persons attempting to cross the international border without a warrant or any particularized suspicion of unlawful activity. But a border search that extends beyond a routine search and inspection may require at least reasonable suspicion. The Supreme Court has not precisely defined the scope of a routine border search, but has suggested that highly intrusive searches may fall outside that category and thus require heightened suspicion to withstand Fourth Amendment scrutiny. Thus, the Court has held that the prolonged detention of an airplane traveler pending invasive medical tests required reasonable suspicion that the traveler was a drug smuggler. Conversely, the Court has determined that the removal and disassembly of a fuel tank constituted a routine border search where reasonable suspicion of unlawful activity was not required. The Supreme Court and lower courts have applied this border search exception not only to the physical border itself, but also to searches at the border’s “functional equivalent,” such as at a port of entry in the interior of the United States (e.g., an international airport). Border-related searches and seizures in areas beyond the border or its functional equivalent are generally subject to greater Fourth Amendment scrutiny. For example, government officers may conduct warrantless “extended border searches” of individuals found within the United States if there is both reasonable certainty of a recent border crossing and reasonable suspicion of unlawful activity. Government officers may also conduct certain warrantless searches near the border that do not require evidence of a border crossing. For instance, “roving patrol” stops of vehicles near the border to question the vehicle’s occupants are permissible if there is reasonable suspicion of unlawful activity, while probable cause is required to search the vehicle for contraband or other evidence of a crime. And while vehicle stops at fixed immigration checkpoints are permissible without individualized suspicion, government officers must have probable cause to search vehicles at those checkpoints. In addition, government officers may board vessels in interior or coastal waterways to conduct routine document and safety inspections, but may require at least reasonable suspicion to conduct more intrusive searches of the vessel. Recent years have seen legal challenges to border searches of electronic devices such as cell phones and computers, which often contain more personal and sensitive information than other items frequently searched at the border, such as a wallet or briefcase. The Supreme Court has not yet addressed this issue. Lower courts have generally held that government officers may conduct relatively limited, manual searches of such devices without a warrant or any particularized suspicion. The courts, however, are split over whether more intrusive, forensic searches require at least reasonable suspicion. Additionally, there is some debate over warrantless drone surveillance at the border and surrounding areas, given a drone’s potential capability to access more information about a person than other forms of aerial surveillance. Another emerging issue concerns the use of biometrics, particularly the collection of DNA samples from detained aliens at the border. Apart from these issues, there have also been concerns about the use of “racial profiling” during investigatory stops near the border. Legislation introduced in recent Congresses would clarify the government’s ability to conduct searches and seizures at the border and surrounding regions. Congressional Research Service Searches and Seizures at the Border and the Fourth Amendment Contents Constitutional Authority Over the Border ....................................................................................... 3 Federal Statutory and Regulatory Framework for Searches and Seizures at or Near the Border ........................................................................................................................................... 4 Federal Customs Statutes and Regulations ............................................................................... 5 Customs Officers’ Authority ............................................................................................... 5 Coast Guard Authority ........................................................................................................ 7 Federal Immigration Laws and Regulations ............................................................................. 7 Border Searches and the Fourth Amendment ................................................................................ 12 General Overview of the Fourth Amendment ......................................................................... 12 “The People” Protected by the Fourth Amendment .......................................................... 13 Searches ............................................................................................................................ 16 Seizures ............................................................................................................................. 17 Standards of Suspicion: Probable Cause and Reasonable Suspicion ................................ 18 Warrantless Searches and Seizures ................................................................................... 19 Searches at International Borders ............................................................................................ 19 The Border and Its Functional Equivalent ........................................................................ 20 Searches and Seizures: Routine and Nonroutine .............................................................. 21 Other Exceptions to the Fourth Amendment’s Warrant Requirement That May Be Relevant to Encounters Near the Border .............................................................................. 25 Warrantless Arrests ........................................................................................................... 27 Government Searches Beyond the Border and Its Functional Equivalent .................................... 28 Extended Border Searches ...................................................................................................... 28 Boarding and Inspection of Vessels Within Interior and Coastal Waterways ......................... 31 United States v. Villamonte-Marquez ............................................................................... 32 Lower Courts’ Decisions on Boarding of Vessels ............................................................. 33 Roving Patrols ......................................................................................................................... 34 Almeida-Sanchez v. United States .................................................................................... 35 United States v. Brignoni-Ponce ....................................................................................... 35 United States v. Cortez ...................................................................................................... 37 United States. v. Arvizu .................................................................................................... 37 Lower Court Decisions on Roving Patrols ....................................................................... 38 Fixed Immigration Checkpoints .............................................................................................. 39 United States v. Martinez-Fuerte ...................................................................................... 40 United States v. Ortiz ........................................................................................................ 41 Lower Court Decisions on Immigration