Arizona v. Johnson

Following is the case brief for Arizona v. Johnson, Supreme Court of the United States, (2009)

Case summary for Arizona v. Johnson:

  • Johnson was a passenger in a vehicle legally seized for a traffic stop.
  • One officer developed suspicion that Johnson was carrying a gun and ordered him out of the car, where she performed a pat down (frisk). The pat down unveiled a gun.
  • Johnson challenged the constitutionality of the search and the trial court found in his favor.
  • The Court overturned the lower court’s ruling, stating that during a lawful traffic stop, an officer only needs a reasonable suspicion to perform a pat down on the driver or passengers of the vehicle.

Arizona v. Johnson Case Brief

Statement of the facts:

Once officers found out that a vehicle’s registration had been suspended, they performed a valid traffic stop. Johnson, who was riding in the car as a passenger, was asked to step outside of the vehicle. Out of fear that Johnson may have had a gun, one of the officers performed a frisk which led to the discovery of a gun. At trial, the state court found that the search was unconstitutional since the officer failed to establish a suspicion that Johnson was connected to criminal activity.

Procedural History:

In response, the state appealed and the Supreme Court of the United States granted certiorari.

Rule of Law or Legal Principle Applied:

An officer must have a reasonable suspicion that the driver or passenger of a lawful traffic stop is armed and dangerous in order to perform a frisk.

Issue and Holding:

During a traffic stop, may an officer frisk a vehicle’s passenger based on a suspicion that the suspect upon which the frisk is performed is armed and dangerous? Yes.


The Court reversed the lower Court’s decision.


(Unanimous) During a traffic stop, an officer must establish a reasonable suspicion that the suspect is armed and dangerous in order to justify a pat down of a driver or passenger. Here, frisking Johnson was constitutional.

Officer inquiries do not terminate the lawful seizure. None of the officers indicated that Johnson was free to go or that the seizure had terminated. In addition, one of the officers established reasonable suspicion that she thought Johnson had a gun. As a result, this reasonable suspicion that Johnson was armed, developed during a lawful traffic stop makes the frisk constitutional.


This case established the foundation for performing a pat down during a traffic stop. The belief that the suspect is involved in criminal activity is not necessary. The officer must have reasonable suspicion that the suspect is armed and dangerous.

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