"Without additional reasonable suspicion, the officer must allow the seized person to depart once the purpose of the stop has concluded," Justice Ruth Bader Ginsburg wrote in the majority opinion.
The 6-3 decision in Rodriguez v. United States stems from a case in which a Nebraska police officer waited seven to eight minutes in between issuing a written warning and walking a drug-sniffing dog around a vehicle. The dog turned up a "large bag" of methamphetamine. Operating on what a magistrate judge earlier called "a rather large hunch," Officer Morgan Struble asked permission from the driver, Dennys Rodriguez, to bring the canine around the vehicle. When Rodriguez declined, Struble called for a backup deputy.
While he awaited his arrival on the scene, Struble testified that he got the paperwork "out of the way." He considered the purpose of the stop complete, yet the motorist was not free to leave. Once his backup arrived, Struble led the dog around the vehicle.
Lower courts had found that a wait of less than ten minutes constituted only a minimal intrusion on the driver's Fourth Amendment rights, which prohibit unreasonable search and seizure, and therefore did not outweigh the government's compelling interest in thwarting the illegal-drug trade. But Tuesday, the Supreme Court said the duration of the stop could only last as long as necessary to conclude its purpose. "The critical question is not whether the dog sniff occurs before or after the officer issues a ticket, but whether conducting the sniff adds time to the stop," Ginsburg wrote.
Law enforcement officials expressed concern that Tuesday's ruling could have the opposite of the intended effect. Rather than ensure traffic stops are conducted as efficiently as possible, officers could lengthen the time it takes to complete paperwork and necessary background checks.
"We're not promoting that, but is this not going to prolong traffic stops?" asked Greg Champagne, a vice president with the National Sheriffs' Association and sheriff in St. Charles Parish, Louisiana. "A police officer is going to say now, 'I really want to run this dog and I want to wait for backup, so now I'm going to sit here and take my time checking their criminal history and take my time writing the ticket just to avoid a finding that this is not unreasonable.'"
More importantly, he worried the ruling could pressure officers to choose expediency at the risk of their own safety. Officers are trained to not turn their backs on suspects, particularly in a stop like the Rodriguez case, where there was also a passenger in the vehicle. With the ruling, officers may choose to not wait for backup.
That is a concern shared by Justice Samuel Alito. In his dissent, he wrote that "Office Struble's error – apparently – was following prudent procedures motivated by legitimate safety concerns." Justices Clarence Thomas and Anthony Kennedy joined Alito in dissenting.
Despite the ruling, Rodriguez isn't off the hook. The Supreme Court only examined the issue of whether police officers could keep him detained beyond the scope of the moving violation. They didn't address whether Struble had reasonable suspicion to conduct the search. That determination has been remanded to the Eighth Circuit.