Facts of the Case
U.S. Border Patrol agent Clinton Stoddard was working a checkpoint on U.S. Highway 191 north of Douglas, Arizona on an afternoon in January 1998. In this area, the roads are equipped with sensors to alert agents to the presence of traffic on infrequently traveled roads, a sign that smugglers of drugs or aliens might be in the area. At 2:15 p.m., a car passing on a nearby road tripped a sensor, and Stoddard went to investigate. Agents typically changed shifts around this time.
The United States Border Patrol (USBP) is an American federal law enforcement agency whose mission is to detect and prevent illegal aliens, terrorists and terrorist weapons from entering the United States, and prevent illegal trafficking of people and contraband. It is the mobile, uniformed law enforcement arm of U.S. Customs and Border Protection (CBP), a component of the United States Department of Homeland Security (DHS).
Douglas is a city in Cochise County, Arizona, United States that lies in the north-west to south-east running San Bernardino Valley within which runs the Rio San Bernardino. Douglas has a border crossing with Mexico at Agua Prieta and a history of mining.
Stoddard found the vehicle that tripped the sensor. It was a minivan, the sort of car that smugglers use to transport their cargo. As it approached Stoddard, it slowed dramatically, from about 55 miles per hour to about 30. An adult man was driving. His posture was rigid, and he conspicuously ignored Stoddard as Stoddard passed by. Stoddard found this behavior suspicious because most drivers in the area wave at passing motorists. Stoddard also noticed children sitting in the back seat of the minivan. Their knees were propped up high, as if their feet were resting on something on the floor. At this point, Stoddard pulled alongside the car. The children in the back seat started to wave at Stoddard in a peculiar manner. As Stoddard was driving alongside the car, the driver abruptly signaled a turn onto the last available road that would avoid the checkpoint. Stoddard radioed for a registration check on the minivan, and found out that it was registered to an address in Douglas known for heavy narcotics trafficking. At this point Stoddard stopped the minivan. Stoddard learned that the driver's name was Ralph Arvizu. Stoddard asked Arvizu for permission to search the van, and found almost 129 pounds of marijuana.
Arvizu was charged in district court with possession of marijuana with intent to distribute. In federal court, he asked to suppress the marijuana, arguing that Stoddard did not have reasonable suspicion to stop him. Citing these facts and the circuitous nature of the route Arvizu was taking from Douglas to nearby Tucson, the district court denied Arvizu's suppression motion.
Reasonable suspicion is a legal standard of proof in United States law that is less than probable cause, the legal standard for arrests and warrants, but more than an "inchoate and unparticularized suspicion or 'hunch'"; it must be based on "specific and articulable facts", "taken together with rational inferences from those facts", and the suspicion must be associated with the specific individual. If police additionally have reasonable suspicion that a person so detained is armed and dangerous, they may "frisk" the person for weapons, but not for contraband like drugs. Reasonable suspicion is evaluated using the "reasonable person" or "reasonable officer" standard, in which said person in the same circumstances could reasonably suspect a person has been, is, or is about to be engaged in criminal activity; it depends upon the totality of circumstances, and can result from a combination of particular facts, even if each is individually innocuous.
Arvizu appealed to the Ninth Circuit. After analyzing each of the 10 factors relied on by the district court in isolation, the Ninth Circuit concluded that seven of the 10 factors were susceptible of an innocent explanation and thus carried little or no weight in the reasonable-suspicion analysis. The remaining factors—the fact that the route was frequently traveled by smugglers, the timing of the alert relative to the agents' shift change, and the fact that Arvizu was driving a minivan—did not render the stop permissible. Consequently, the court reversed Arvizu's conviction. The government appealed to the Supreme Court.
Terry v. Ohio, 392 U.S. 1 (1968), was a decision by the United States Supreme Court which held that the Fourth Amendment prohibition on unreasonable searches and seizures is not violated when a police officer stops a suspect on the street and frisks him or her without probable cause to arrest, if the police officer has a reasonable suspicion that the person has committed, is committing, or is about to commit a crime and has a reasonable belief that the person "may be armed and presently dangerous."
A Terry stop in the United States allows the police to briefly detain a person based on reasonable suspicion of involvement in criminal activity. Reasonable suspicion is a lower standard than probable cause which is needed for arrest. When police stop and search a pedestrian, this is commonly known as a stop and frisk. When police stop an automobile, this is known as a traffic stop. If the police stop a motor vehicle on minor infringements in order to investigate other suspected criminal activity, this is known as a pretextual stop. Additional rules apply to stops that occur on a bus.
Illinois v. Gates, 462 U.S. 213 (1983), is a Fourth Amendment case. Gates overruled Aguilar v. Texas and Spinelli v. United States, thereby replacing the Aguilar–Spinelli test for probable cause with the "totality of the circumstances" test.
United States v. Montoya De Hernandez, 473 U.S. 531 (1985), was a U.S. Supreme Court case regarding the Fourth Amendment's border search exception and balloon swallowing.
Illinois v. Caballes, 543 U.S. 405 (2005), was a United States Supreme Court case in which the Court held that the Fourth Amendment is not violated when the use of a drug-sniffing dog during a routine traffic stop does not unreasonably prolong the length of the stop.
Consent searches are searches made by police officers in the United States based on the voluntary consent of the individual whose person or property is being searched. The simplest and most common type of warrantless searches in the United States are searches based upon consent. No warrant, probable cause or reasonable suspicion is required to perform a search if a person, or someone else with the proper authority, consents to a search.
Ohio v. Robinette, 519 U.S. 33 (1996), was a United States Supreme Court case in which the Court held that the Fourth Amendment does not require police officers to inform a motorist at the end of a traffic stop that they are free to go before seeking permission to search the motorist's car.
Florida v. Royer, 460 U.S. 491 (1983), was a U.S. Supreme Court case dealing with issues involving the Fourth Amendment. Specifically, the case establishes a firm line in cases where police conduct search and seizure without a warrant. The court ruled that, while it is legal for authorities to target and approach a person based on their behavior, absent more, they cannot detain or search such individual without a warrant.
United States v. Flores-Montano, 541 U.S. 149 (2004), was a United States Supreme Court case in which the Court held that customs agents may remove the gas tank from a vehicle crossing the international border in an effort to look for contraband.
Brendlin v. California, 551 U.S. 249 (2007), was a decision by the Supreme Court of the United States that held that all occupants of a car are "seized" for purposes of the Fourth Amendment during a traffic stop, not just the driver.
Kolender v. Lawson, 461 U.S. 352 (1983), is a United States Supreme Court case concerning the constitutionality of vague laws that allow police to demand that "loiterers" and "wanderers" provide identification.
In United States criminal law, the border search exception or doctrine is a doctrine that allows searches and seizures at international borders and their functional equivalent without a warrant or probable cause. The doctrine is not regarded as an exception to the Fourth Amendment, but rather to its requirement for a warrant or probable cause. Balanced against the sovereign's interests at the border are the Fourth Amendment rights of entrants. Not only is the expectation of privacy less at the border than in the interior, the Fourth Amendment balance between the interests of the government and the privacy right of the individual is also struck much more favorably to the government at the border. This balance at international borders means that routine searches are "reasonable" there, and therefore do not violate the Fourth Amendment's proscription against "unreasonable searches and seizures".
Illinois v. Lidster, 540 U.S. 419 (2004), was a case in which the Supreme Court of the United States ruled that the Fourth Amendment permits the police to use a roadblock to investigate a traffic incident.
United States v. Brignoni-Ponce, 422 U.S. 873 (1975), was the case in which the Supreme Court determined it was a violation of the Fourth Amendment for a roving patrol car to stop a vehicle solely on the basis of the driver appearing to be of Mexican descent. A roving patrol car must have articulable facts that allow for an officer to have a reasonable suspicion that the person is carrying illegal aliens beyond their ethnicity. The Court handed down a 9-0 decision that affirmed the Circuit Court’s ruling in the case.
United States v. Martinez-Fuerte, 428 U.S. 543 (1976), was a decision of the United States Supreme Court that allowed the United States Border Patrol to set up permanent or fixed checkpoints on public highways leading to or away from the Mexican border and that the checkpoints are not a violation of the Fourth Amendment.
Whren v. United States, 517 U.S. 806 (1996), was a unanimous United States Supreme Court decision that "declared that any traffic offense committed by a driver was a legitimate legal basis for a stop."
Navarette v. California, 572 U.S. 393 (2014), was a case in which the United States Supreme Court clarified when police officers may make arrests or conduct temporary detentions based on information provided by anonymous tips. In 2008, police in California received a 911 call that a pickup truck was driving recklessly along a rural highway. Officers spotted a truck matching the description provided in the 911 call and followed the truck for five minutes, but did not observe any suspicious behavior. Nevertheless, officers conducted a traffic stop and discovered 30 pounds (14 kg) of marijuana in the truck. At trial, the occupants of the car argued that the traffic stop violated the Fourth Amendment of the United States Constitution, because the tip was unreliable, and officers did not personally observe criminal activity. Writing for a majority of the Court, Justice Clarence Thomas held that the 911 call was reliable, and that officers need not personally observe criminal activity when acting upon information provided by an anonymous 911 call.
