What are the relevant factors for a stop and detention under the Fourth Amendment?

The Fourth Amendment "applies to all seizures of the person, including seizures that involve only a brief detention short of traditional arrest." United States v. Brignoni-Ponce, 422 U.S. 873, 878 (1975). Accordingly, the Fourth Amendment requires that such seizures be, at a minimum, "reasonable." Id. An investigatory stop of a vehicle may be based upon a reasonable suspicion that criminal activity is afoot upon an evaluation of the totality of the circumstances. United States v. Arivizu, 534 U.S. 266 (2002). The evaluation precludes a "divide-and-conquer analysis" because even though each of the suspect's "acts was perhaps innocent in itself . . . taken together, they [may] warrant [] further investigation." Id. at 274. The analysis allows officers to draw on their own experience and specialized training to make inferences from and deductions about the cumulative information available to them that might elude an untrained person. Id.

Under United States v. Brignoni-Ponce, 422 U.S. at 884, a non-exclusive list of factors a court may use in determining whether a stop and detention is lawful includes: (1) characteristics of the area where vehicle encountered; (2) proximity to border; (3) erratic or evasive driving; aspects of the vehicle; and (4) behavior of the driver. Such facts must be filtered through the lens of the agent's training and experience. Id. at 885.

The relevant factors in this case are as follows: