Extension of Traffic Stops for K-9 Sniffs Requires Specific Reasonable Suspicion

Introduction

Thompson v. Richter, decided April 29, 2025 by the Fifth Circuit, addresses two interrelated legal questions: (1) whether the Texas Department of Public Safety (TDPS) may be compelled to comply with third-party discovery subpoenas over its sovereign immunity objection; and (2) whether Troopers Will Richter and Mark Strange are entitled to qualified immunity for extending a routine speeding stop to permit a canine “free-air sniff” and a subsequent search that uncovered drugs and a firearm. Plaintiffs Russell Thompson and Demetrius McChester were stopped on Route 287 for speeding in September 2020. After routine questioning and a denied consent to search, Trooper Richter summoned a K-9 unit, extending the stop by roughly 26 minutes until the dog arrived and alerted. A search followed, leading to an arrest for marijuana possession and weapons offenses. The district court quashed the subpoenas against TDPS on Eleventh Amendment grounds and granted qualified immunity to the troopers. Plaintiffs appealed both holdings.

Summary of the Judgment

The Fifth Circuit issued a per curiam, unpublished opinion affirming the district court in all respects. First, the court held that as an agency of the State of Texas, TDPS is immune from compelled discovery under the Eleventh Amendment absent an unequivocal waiver, which was not present here. Second, the panel applied the two-step Terry analysis for traffic stops and the Supreme Court’s qualified immunity framework. It found that: (a) the stop was lawful at inception because of speeding; (b) Richter’s initial ten-minute questioning fell within permissible traffic-stop “Terry” parameters; (c) the extension to await a K-9 unit was supported by specific, articulable facts—namely, inconsistencies between the travelers’ stories, indicia of evasiveness, travel along a known drug corridor, mismatched GPS directions, and lingering reasonable suspicion; and (d) no Fifth Circuit or Supreme Court precedent “placed the unlawfulness of Richter’s actions beyond debate” in April 2020. Accordingly, both troopers were entitled to qualified immunity, and plaintiffs had not shown a clearly established Fourth Amendment violation.

Analysis

1. Precedents Cited

• Terry v. Ohio (1968) – established the two-part reasonableness test for stops and frisks (justification at inception; scope reasonably related to the circumstances).
• Rodriguez v. United States (2015) – held that a dog sniff that prolongs an otherwise completed stop violates the Fourth Amendment absent reasonable suspicion.
• Illinois v. Caballes (2005) – approved a dog sniff conducted during a legitimate traffic-stop duration without extending the stop.
• United States v. Brigham (5th Cir. 2004) – held that routine traffic-stop questioning for up to ten minutes is permissible; applies the Terry framework to traffic stops.
• United States v. Estrada (5th Cir. 2006) – clarified that officers may ask questions unrelated to the traffic violation within the initial ten-minute window.
• Russell v. Jones (5th Cir. 2022) – reaffirmed that sovereign immunity bars compelled compliance with a subpoena duces tecum.
• Weisshaus v. Teichelman (5th Cir. 2024) – recently held that travel on a drug corridor plus evasive answers and other factors can support reasonable suspicion to extend the stop for a dog sniff.

2. Legal Reasoning

Eleventh Amendment / Sovereign Immunity: The court reiterated that state agencies like TDPS enjoy absolute immunity from third-party discovery subpoenas absent an “unequivocal” waiver. Participation in any portion of discovery does not equate to waiver. Plaintiffs’ arguments that TDPS had “opened itself” to discovery by supplying records to the troopers were rejected in light of binding Fifth Circuit authority.

Qualified Immunity Framework: Under Harlow v. Fitzgerald, officers are shielded unless (a) their conduct violated a constitutional right and (b) that right was clearly established at the time. The Fifth Circuit limits its inquiry on summary judgment to whether the plaintiffs identified binding precedent placing the alleged misconduct “beyond debate.”

Fourth Amendment / Traffic-Stop Extension: Applying Terry, the court confirmed that Richter had a legal basis to stop for speeding and to ask preliminary questions within ten minutes. The critical issue was the additional 26-minute delay awaiting the K-9. Drawing on recent decisions, the panel identified multiple articulable facts giving rise to “reasonable suspicion” of narcotics trafficking: conflicting accounts of origin and destination (mismatch with GPS), nervous behavior in a chilly morning setting, temporary registration and insurance irregularities, travel on a known drug corridor in the early hours, and the officer’s experience-based inferences. Because those factors together satisfied the standard for prolonging a detention to conduct a sniff— and because no controlling precedent clearly prohibited such an extension— Richter and Strange retained qualified immunity.

3. Impact

Thompson v. Richter underscores that extensions of traffic stops for drug-detection dog sniffs do not infringe the Fourth Amendment so long as the officer can point to case-specific, articulable facts raising reasonable suspicion. Routine questioning within ten minutes remains secure, and the deferential qualified immunity standard demands closely analogous precedent to defeat it. Future litigants will need to show that facts more egregious than those here were previously deemed unconstitutional or that courts have already condemned lengthy delays for canine inspections under similar profiles of nervousness, inconsistent stories, and geographic risk factors.

Complex Concepts Simplified

• Terry Stop: A brief investigatory detention justified by reasonable suspicion of wrongdoing.
• Reasonable Suspicion vs. Probable Cause: Reasonable suspicion is a lower threshold, requiring specific, articulable facts that criminal activity may be afoot; it suffices for a short detention but not for full arrest.
• Qualified Immunity: A doctrine protecting officers from civil liability unless they violated a “clearly established” right—i.e., a right so well defined that every reasonable officer would know his conduct was unlawful.
• Sovereign Immunity (Eleventh Amendment): A constitutional shield that prevents states and state agencies from being sued or forced to produce documents in federal court absent an unequivocal waiver.

Conclusion

Thompson v. Richter makes clear that: (1) state agencies cannot be compelled to respond to third-party subpoenas without an express waiver of sovereign immunity; and (2) law enforcement officers may lawfully extend a speeding stop to await a K-9 sniff when they have case-specific reasonable suspicion—such as inconsistent travel stories, signs of evasion, location on a known drug corridor, and conflicting GPS information—and no binding precedent puts those facts “beyond debate.” The decision reaffirms the balance between traffic-stop investigatory authority and constitutional safeguards, while illustrating the rigorous demands of the qualified immunity standard.