United States v. Sharpe: Diligence, Twenty Minutes, and Terry Stops

In United States v. Sharpe, 470 U.S. 675 (1985), the Supreme Court held that the Fourth Amendment sets no fixed time limit on an investigative stop. What matters is whether the officers diligently pursued a means of investigation likely to confirm or dispel their suspicions quickly. A 20-minute roadside detention was reasonable on the facts before the Court, and the drug evidence found at the end of it was admissible.¹

What Happened on the Highway

DEA Agent Cooke was patrolling a coastal highway in South Carolina when he noticed a Pontiac and a pickup truck with an attached camper traveling in tandem. Both vehicles looked heavily loaded, and the camper was riding low on its springs. After following them for about 20 miles, Cooke decided to make an investigative stop and asked a local officer, Thrasher, to signal both vehicles to pull over.¹

Sharpe, driving the Pontiac, pulled into the right lane. Savage, driving the pickup, cut between the Pontiac and the patrol car and kept going. Thrasher chased the truck and stopped it about half a mile down the road. Cooke stayed with the Pontiac, tried unsuccessfully to reach Thrasher by radio, and called for backup. Two Myrtle Beach officers arrived roughly 10 minutes later. Cooke then drove to the pickup, arriving about 15 minutes after Thrasher had stopped it. At the truck he identified himself, smelled marijuana through the rear camper window, took the keys after Savage refused permission to search twice, and opened the camper. A later inventory recorded 43 burlap-wrapped bales totaling 2,629 pounds of marijuana.²

Reasonable Suspicion Was Not the Fight

Under Terry v. Ohio, an officer can briefly stop and detain a person on reasonable suspicion, grounded in specific and articulable facts, that criminal activity is afoot. That threshold sits below the probable cause required for an arrest.³

Cooke’s observations, two heavily loaded vehicles moving together on a known drug corridor with the camper riding low, gave him enough to initiate the stop. The Supreme Court did not seriously question that. The dispute was about what happened next.

Why the Case Reached the Supreme Court

The Fourth Circuit reversed the convictions. In its view, a 20-minute detention on less than probable cause exceeded the brevity a Terry stop demands, and the delay had transformed the stop into an arrest. Without probable cause at the moment of the stop, the marijuana had to be suppressed.¹

That approach amounted to a bright-line rule: 20 minutes is too long. The Supreme Court granted review to decide whether the Fourth Amendment tolerates that kind of fixed cap on investigative stops.

The Diligence Standard

Chief Justice Burger, writing for six justices, rejected any rigid time limit. The right question, the Court held, is whether the police diligently pursued a means of investigation that was likely to confirm or dispel their suspicions quickly. Courts should look to what the officers actually did during the stop, not to a stopwatch.¹

The Court added that reviewing courts should not engage in unrealistic second-guessing of decisions officers make under pressure. If a less intrusive alternative existed in theory, that alone does not make the chosen approach unreasonable. The test is reasonableness in the situation as it unfolded.

How the Court Applied the Standard to Twenty Minutes

Applied to Cooke and Thrasher, the diligence test came out easily for the government. The vehicles ended up half a mile apart because Savage refused to stop. Cooke could not raise Thrasher on the radio. He called for backup, waited about 10 minutes for the Myrtle Beach officers, and then drove straight to the truck. Nothing in the record showed stalling or unrelated activity. Much of the delay, the Court noted, was caused by the suspects’ own evasive conduct rather than police inefficiency. The 20 minutes was therefore reasonable, and the evidence was admissible.¹

The Separate Opinions

Justice Marshall concurred in the result. He agreed that the delay here was justified because the defendants caused it, but he wrote separately to argue that the majority understated how central brevity is to a Terry stop. In his view, length alone can push a detention past what reasonable suspicion will support, regardless of officer diligence.¹

Justice Brennan dissented. He read the record as showing miscommunication and poor coordination between the officers, and he argued that the majority excused delays a better-run operation would have avoided. To Brennan, the diligence standard was too deferential and too willing to overlook available, less intrusive alternatives.¹

When a Terry Stop Becomes a De Facto Arrest

The Fourth Circuit’s worry in Sharpe was that the stop had crossed into an arrest, which would require probable cause. Courts still evaluate that question by looking at the totality of the circumstances: how long the detention lasted, how many officers were involved, how much physical restraint was used, and whether the suspect was moved from the original scene. Transporting someone to a police station for questioning, for example, has consistently been treated as requiring probable cause.

Officers can take protective measures without automatically turning a stop into an arrest. Drawing weapons, ordering people out of a car, and even brief handcuffing can stay within Terry when officers have legitimate safety concerns. The line moves when the restraint outruns what the investigation reasonably needs.⁴

What Rodriguez Added Thirty Years Later

Sharpe governs stops that run long because the investigation itself takes time. Rodriguez v. United States (2015) answered a different question: can officers hold a driver past the point where the traffic stop’s own tasks are done, in order to pursue something else?⁵

The Court said no. Once the tasks tied to the traffic violation are complete, the authority to detain ends. In Rodriguez, an officer had finished the traffic stop and then held the driver seven or eight extra minutes waiting for a second officer and a drug-sniffing dog. That extension was unconstitutional. A dog sniff is not part of the traffic mission, and an officer cannot bank time saved on the traffic tasks to spend on an unrelated criminal investigation.⁵

Read together, the two cases form a workable framework. Sharpe says the clock does not run on a fixed timer as long as officers stay focused on the investigation that justified the stop. Rodriguez says the clock stops entirely once the stop’s original purpose is fulfilled, unless independent reasonable suspicion supports going further. Illinois v. Caballes (2005) had already held that a dog sniff during an otherwise lawful traffic stop does not itself violate the Fourth Amendment; Rodriguez clarified that the sniff cannot add any time to the stop.⁶

Consequences When a Stop Runs Too Long

If a court finds a detention lasted beyond what Terry allows, the main remedy is suppression. Evidence obtained during the unlawful portion of the stop cannot be used at trial, and derivative evidence traceable to it is excluded as fruit of the poisonous tree. That is exactly the result the Fourth Circuit had ordered in Sharpe before the Supreme Court reversed: the 2,629 pounds of marijuana would have been out.⁷

Exceptions can keep evidence in play even after a violation. Good-faith reliance on an invalid warrant and inevitable discovery through an independent investigation already underway are the two most commonly invoked.⁷

Why Sharpe Still Matters

Sharpe is the case courts reach for whenever the length of an investigative detention is challenged, in contexts well beyond drug interdiction. The question it forces is not how many minutes passed but how those minutes were used. Officers who work a focused investigation get latitude; officers who let the clock run while looking for something to justify the stop do not.¹

1
Justia U.S. Supreme Court Center. United States v. Sharpe
2
Legal Information Institute. United States v. Sharpe
3
Justia U.S. Supreme Court Center. Terry v. Ohio
4
Justia. Detention Short of Arrest: Stop and Frisk
5
Justia U.S. Supreme Court Center. Rodriguez v. United States
6
Justia U.S. Supreme Court Center. Illinois v. Caballes
7
Legal Information Institute. Exclusionary Rule