Lawful Duration of a Traffic Stop

Two recent cases have ruled on the lawful duration of a traffic stop:

United States v. Bowman:  Duration of a traffic stop. (4th Circuit)
It was undisputed that the initial traffic stop was complete when the officer issued Bowman a warning citation, returned his documents, and shook his hand. It was also undisputed that Bowman consented to the officer’s request to answer additional questions, which the officer did for approximately 40 seconds. However, the court concluded that this brief consensual encounter became a Fourth Amendment seizure when the officer told Bowman to "hang tight". As a result, the court held that the officer unreasonably prolonged the duration of the traffic stop; therefore, the district court should have suppressed the evidence recovered from [the] vehicle.

United States v. Rodriguez-Escalera:  Duration of a traffic stop. (7th Circuit)
While the court recognized that an officer does not need to rule out a suspect’s explanation for conduct that appears to be suspicious at first, a court may consider how facts later obtained confirm or dispel that initial suspicion. The court added that no criminal history, tips, or surveillance supported the trooper’s suspicions. Based on these facts, the court concluded that the trooper did not establish reasonable suspicion of criminal activity during the stop. Consequently, the court held that it was unreasonable to detain [the vehicle] beyond the time needed to complete the original purpose of the traffic stop because the only on-duty K-9 was busy with another stop.

In a previous case, Rodriguez v. United States, 135 S. Ct. 1609 (2015),  the U.S. Supreme Court stressed that a seizure justified only by a police-observed traffic violation becomes unlawful if it is prolonged beyond the time reasonably required to complete the mission of issuing a ticket for the violation. The stop may not exceed the time needed to handle the matter for which the stop was made. In Rodriguez, the issue was raised in the context of whether the police unnecessarily extended the traffic-violation stop to conduct a dog sniff of the exterior of the vehicle for drugs.

Lower courts applying Rodriguez have had the difficult task of determining whether a vehicle stop for a traffic violation was unnecessarily and unlawfully prolonged by police so that they could pursue unrelated suspicions, usually related to illegal drugs. While the courts often observe that there is no rigid time limit for determining when a detention has lasted longer than necessary to effectuate the purposes of the stop, they nevertheless often look to the total time of the stop and the length of what is deemed the unnecessary delay in determining whether the police conduct was lawful. In State v. Linze, No. 42321, 2016 WL 90669 (Idaho Ct. App. Jan. 8, 2016), the court held that where the police extended a routine traffic stop (that lasted 19 minutes) by only approximately another two and a half minutes to conduct a dog sniff (or canine sweep) of the vehicle, such delay was unlawful and violated the driver's Fourth Amendment rights.

"A police stop exceeding the time needed to handle the matter for which the stop was made violates the Constitution’s shield against unreasonable seizures," Justice Ruth Bader Ginsburg wrote for the majority. The vote was 6 to 3.

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Although written for Washington State, the publication "Traffic Stops in Washington: A Judge's Bench Book" provides guidance for citizens in every state wishing to understand traffic stops and what courts (WA Courts) consider when hearing cases arising from a traffic stop.

The Seattle Police Department Manual - Section 6.220 - Voluntary Contacts, Terry Stops & Detentions is also informative, and included some things that I found surprising, such as:

• Officers Cannot Require Subjects to Identify Themselves or Answer Questions on a Terry Stop.
• Under [WA] State Law, Traffic Violations May Not Be Used as a Pretext to Investigate Unrelated Crimes for Which the Officer Lacks Reasonable Suspicion.