What Does the Constitution Say About Traffic Stops?

Seizure is a critical constitutional topic in the context of driving a car because it normally initiates the citizen-government encounter. The Fourth Amendment to the United States Constitution protects “[t]he right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures.”[1] “The Fourth Amendment applies to all seizures of the person, including seizures that involve only a brief detention short of traditional arrest.”[2]  The act, by police, of “stopping an automobile and detaining its occupants” has been recognized, by the Supreme Court, as a seizure.[3]

Traffic stops are considered seizures of the vehicle, all persons, and things therein for constitutional purposes. Such seizures must be made pursuant to reasonable suspicion that a violation of the law has occurred.[4] This is a lesser standard than the probable cause that is required for an arrest to be made.[5]

On multiple occasions, the Supreme Court has taken up the question of what constitutes reasonable suspicion for a valid traffic stop. Anonymous tips, that include facts giving rise to a degree credibility, have been sufficient to justify traffic stops.[6] Calls from other motorists reporting potentially dangerous behavior, have also been deemed to justify a traffic stop even when the officer does not personally observe the behavior.[7]

When a police officer stops a vehicle, the scope of the seizure can be broader than just the car and its driver. The Supreme Court has held that “[a] seizure occurs even when an unintended person or thing is the object of the detention or taking . . . .”[8] In Brendlin v. California, the passenger in a vehicle sought to suppress drugs found on his person.[9]Brendlin argued that police unlawfully stopped the vehicle, thus his seizure was unconstitutional.[10] The State of California argued that Brendlin was not seized by the traffic stop because he was a passenger and, therefore, could not suppress evidence based on an unlawful seizure.[11] The state courts of California went back and forth on what degree of protection the Constitution afforded Brendlin as a passenger.[12] After granting certiorari, the United States Supreme Court held that based on the nature of a traffic stop, all occupants of the vehicle are seized for constitutional purposes.[13]

It has also been deemed reasonable, in the Court’s eyes, for police to order the driver and passengers out of a vehicle.[14] In Pennsylvania v. Mimms, police stopped Mimms after they observed him driving a vehicle that displayed an expired license plate.[15] Police then ordered Mimms out of the car and arrested him when they observed a gun in his waistband.[16] The Supreme Court of Pennsylvania reversed his conviction after finding that the act of ordering Mimms out of the car was an unconstitutional seizure. The United States Supreme Court disagreed and held that “[w]hat is at most a mere inconvenience cannot prevail when balanced against legitimate concerns for the officer’s safety.”[17]

Similarly, in Maryland v. Wilson, police stopped a vehicle in which Wilson was a passenger.[18] The officer ordered Wilson to exit from the passenger seat after observing his suspicious behavior.[19] When Wilson got out of the vehicle, “a quantity of crack cocaine fell to the ground.”[20] The Supreme Court held that Pennsylvania v. Mimms gives police the authority to order drivers and passengers out of a lawfully stopped car.[21]

Given the low standard of reasonable suspicion, police can justify traffic stops through a variety of means. Even violations of trivial municipal ordinances can justify seizure in the form of a traffic stop.[22] The violation used to justify the stop does not necessarily have to be the officer’s sole motivation for stopping a vehicle.[23] This was the case in Whren v. United States when “[p]lainclothes policemen patrolling a ‘high drug area’ in an unmarked vehicle” stopped a vehicle for a traffic offense and subsequently arrested the occupants for a drug offense.[24] The Supreme Court held that “temporary detention of a motorist upon probable cause to believe that he has violated the traffic laws does not violate the Fourth Amendment’s prohibition against unreasonable seizures, even if a reasonable officer would not have stopped the motorist absent some additional law enforcement objective.”[25]

On the other hand, the Supreme Court has identified several cases in which decisions by law enforcement to stop vehicles were not justified by reasonable suspicion. A traffic stop cannot be made solely on the premise of checking a driver’s license or registration absent additional suspicion of a violation.[26] Traffic stops also cannot be made solely on the ethnicity of the driver even if the stop occurs near a border.[27] An exception to the requirement of reasonable suspicion lies in certain types of vehicle checkpoints designed to detect specific dangers.[28]

An individual has not been seized until they have submitted to an intentional assertion of police authority.[29]Submission to authority must be gained reasonably. In a case where police used a semitruck, concealed by a curve, to block a roadway and caused a fleeing driver to crash and die, the Supreme Court deemed that a seizure had been effected.[30] They remanded the case for the lower court to determine, then, if the seizure was reasonable.[31]

Traffic Stops, as seizures, must be reasonable in both their scope and means. While there is no set duration for a reasonable traffic stop, it must be consistent with addressing the suspicion of the officer. The Court has held that keeping a driver seven minutes past the issuance of a citation to allow a drug sniff to be conducted by a police canine, absent reasonable suspicion of drugs in the car, was unreasonable.[32] However, in United States v. Sharpe, extending a stop by 15 minutes for another officer to arrive and verify whether the driver was a suspect in a crime was permissible because the officers were acting reasonably.[33]

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[1] Fourth Amendment

[2] United States v. Brignoni-Ponce, 422 U.S. 873, 878 (1975) (citing Davis v. Mississippi, 394 U.S. 721 (1969); Terry v. Ohio, 392 U.S. 1, 16-19 (1968)).

[3] Delaware v. Prouse, 440 U.S. 648, 653 (1979).

[4] United States v. Brignoni-Ponce, 422 U.S. 873, 881 (1975).

[5] Id.

[6] See Alabama v. White, 496 U.S. 325 (1990).

[7] See Navarette v. California, 572 U.S. 393 (2014).

[8] Brendlin v. California, 551 U.S. 249 (2007).

[9] Id.

[10] Id. at 253.

[11] Id. at 256.

[12] Id. at 253-54.

[13] Id. at 258-59.

[14] See Pennsylvania v. Mimms, 434 U.S. 106 (1977); see Maryland v. Wilson, 519 U.S. 408 (1997).

[15] Pennsylvania v. Mimms, 434 U.S. 106, 107 (1977).

[16] Pennsylvania v. Mimms, 434 U.S. 106, 107 (1977).

[17] Pennsylvania v. Mimms, 434 U.S. 106, 111 (1977).

[18] Maryland v. Wilson, 519 U.S. 408, 410 (1997).

[19] Maryland v. Wilson, 519 U.S. 408, 411 (1997).

[20] Maryland v. Wilson, 519 U.S. 408, 411 (1997).

[21] Maryland v. Wilson, 519 U.S. 408, 410 (1997).

[22] See Atwater v. City of Lago Vista, 532 U.S. 318 (2001).

[23] See Whren v. United States, 517 U.S. 806 (1996).

[24] Whren v. United States, 517 U.S. 806 (1996).

[25] Whren v. United States, 517 U.S. 806 (1996).

[26] Delaware v. Prouse, 440 U.S. 648, 663 (1979).

[27] United States v. Brignoni-Ponce, 422 U.S. 873, 886-87 (1975).

[28] See Mich. Dep’t of State Police v. Sitz, 496 U.S. 444, 455 (1990).

[29] California v. Hodari D., 499 U.S. 621, 629 (1991).

[30] Brower v. Cty. of Inyo, 489 U.S. 593, 599 (1989).

[31] Id.

[32] See Rodriguez v. United States, 135 S. Ct. 1609 (2015).

[33] United States v. Sharpe, 470 U.S. 675 (1985).

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