Almeida-Sanchez v. United States - 413 U.S. 266, 93 S. Ct. 2535 (1973)

Rule:

Travellers may be so stopped in crossing an international boundary because of national self protection reasonably requiring one entering the country to identify himself as entitled to come in, and his belongings as effects which may be lawfully brought in. But those lawfully within the country, entitled to use the public highways, have a right to free passage without interruption or search unless there is known to a competent official authorized to search, probable cause for believing that their vehicles are carrying contraband or illegal merchandise.

Facts:

Petitioner, a Mexican citizen and holder of a valid work permit, challenged the constitutionality of the Border Patrol's warrantless search of his automobile 25 air miles north of the Mexican border. The search, made without probable cause or consent, uncovered marihuana, which was used to convict petitioner of a federal crime. The Government sought to justify the search on the basis of § 287 (a)(3) of the Immigration and Nationality Act, which provided for warrantless searches of automobiles and other conveyances "within a reasonable distance from any external boundary of the United States," as authorized by regulations to be promulgated by the Attorney General. The Attorney General's regulation defined "reasonable distance" as "within 100 air miles from any external boundary of the United States." The Court of Appeals upheld the search on the basis of the Act and regulation. Petitioner appealed. 

Issue:

Was the warrantless search of the petitioner’s automobile violative of the Fourth Amendment? 

Answer:

Yes.

Conclusion:

The Court reversed the judgment of the appeals court because in the absence of probable cause or consent, the search violated defendant's U.S. Const. amend. IV right to be free from unreasonable searches and seizures. The Court explained that travellers may be stopped in crossing an international boundary because of national self-protection. But the search of petitioner’s automobile on a California road lying at all points at least 20 miles north of the Mexican border, was of a wholly different sort. Those lawfully within the country and entitled to the use of public highways have a right of free passage without interruption or search, unless a competent official authorized to search has probable cause for believing their vehicles are carrying contraband or illegal merchandise.