Fourth Amendment:

The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.

Congress has broad authority to regulate persons or items entering the United States, an authority rooted in its power to regulate foreign commerce and to protect the integrity of the Nation’s borders.1 Authorized by the First Congress,2 customs searches at the border require no warrant, probable cause, or even a showing of some degree of suspicion that accompanies investigatory stops.3 The Supreme Court has described searches at the international border as “necessary to prevent smuggling and to prevent prohibited articles from entry.” 4 Despite this seemingly broad authority to search persons and items at the border, the Fourth Amendment provides some constraints. The Fourth Amendment generally requires a government officer to secure a warrant based on probable cause before conducting a search or seizure.5 Nonetheless, because the “touchstone” of the Fourth Amendment is reasonableness,6 courts have recognized certain exceptions when the government may engage in a warrantless search or seizure.7

Footnotes

1

See United States v. Montoya de Hernandez, 473 U.S. 531, 538 (1985) (recognizing “Congress’s power to protect the Nation by stopping and examining persons entering this country” ); United States v. 12,200-Foot Reels of Super 8mm. Film, 413 U.S. 123, 125 (1973) ( “The Constitution gives Congress broad, comprehensive powers '(t)o regulate Commerce with foreign Nations.’” ) (quoting U.S. Const. art. I, § 8, cl. 3)).

2

See United States v. Ramsey, 431 U.S. 606, 616 (1977) (noting that Congress “enacted the first customs statute” in 1789).

3

Almeida-Sanchez v. United States, 413 U.S. 266, 272 (1973); United States v. Thirty-Seven Photographs, 402 U.S. 363, 376 (1971); Carroll v. United States, 267 U.S. 132, 154 (1925).

4

12,200-Foot Reels of Super 8mm. Film, 413 U.S. at 125 ( “Historically such broad powers have been necessary to prevent smuggling and to prevent prohibited articles from entry.” ).

5

See Riley v. California, 134 S. Ct. 2473, 2482 (2014) ( “Such a warrant ensures that the inferences to support a search are ‘drawn by a neutral and detached magistrate instead of being judged by the officer engaged in the often competitive enterprise of ferreting out crime.’” ) (quoting Johnson v. United States, 333 U.S. 10, 14 (1948)); Kentucky v. King, 563 U.S. 452, 459 (2011) ( “Although the text of the Fourth Amendment does not specify when a search warrant must be obtained, this Court has inferred that a warrant must generally be secured.” ).

6

See United States v. Knights, 534 U.S. 112, 118–19 (2001) ( “The touchstone of the Fourth Amendment is reasonableness, and the reasonableness of a search is determined ‘by assessing, on the one hand, the degree to which it intrudes upon an individual’s privacy and, on the other, the degree to which it is needed for the promotion of legitimate governmental interests.’” ) (quoting Wyoming v. Houghton, 526 U.S. 295, 300 (1999)).

7

King, 563 U.S. at 459 ( “[B]ecause ‘the ultimate touchstone of the Fourth Amendment is “reasonableness” '. . . [t]he warrant requirement is subject to certain reasonable exceptions.” ) (quoting Brigham City, Utah v. Stuart, 547 U.S. 398, 403 (2006)); Texas v. Brown, 460 U.S. 730, 735 (1983) ( “Our cases hold that procedure by way of a warrant is preferred, although in a wide range of diverse situations we have recognized flexible, common-sense exceptions to this requirement.” ).