The United States Court of Appeals for the Eighth Circuit recently issued a decision in the case of United States v. Rose, where the Court considered whether officers’ observations of tinted windows can establish probable cause for a traffic stop and whether employing a drug-detection dog, along with subsequent arrests and searches, can withstand constitutional scrutiny.[1]
This case originated with a routine traffic stop in Clinton, Iowa, in January 2020. Detective Josh Winter of the Clinton Police Department noticed a vehicle whose front windows appeared to be heavily tinted. Believing that the dark tint violated Iowa law, Detective Winter followed the car, observed it abruptly turn into a parking lot, and conducted a traffic stop. As the car pulled over, the driver, later identified as Johnathon Rose, immediately exited his vehicle. Detective Winter, feeling uneasy because of Rose’s sudden exit, directed him to get back inside. Rose complied but continued to behave in a manner that increased the officer’s concerns. While he gathered Rose’s license, registration, and proof of insurance, Detective Winter contacted dispatch to confirm Rose’s driving status. He also requested that another officer bring a tint meter to measure light transmittance and asked a canine handler, Officer Brennen Roling, to respond, citing facts suggesting Rose was involved with narcotics and firearm trafficking.
When the tint meter arrived, officers confirmed that only a small percentage of light passed through the windows, falling short of the level required by Iowa law. Detective Winter began writing Rose a citation for the tint violation as well as for operating a vehicle without a valid Iowa license. During this process, Officer Roling arrived with a drug-detection dog, and within minutes of starting the sniff, the dog changed its behavior and sat near the front of Rose’s car, which Officer Roling recognized as an alert for the presence of illegal substances. Moments later, the dog alerted again by the passenger door. Noticing these alerts, officers searched the car and discovered suspected drug residue and paraphernalia. Detective Winter then handcuffed Rose and, during a subsequent pat-down, uncovered items that he believed to be ecstasy and THC wax on Rose’s person.
Officers read Rose his Miranda rights in the police vehicle before transporting him to the station. At the station, Rose continued to speak to Detective Winter about the items found in the vehicle. Although Rose did not sign any written waiver, Detective Winter reiterated the Miranda warnings, and Rose proceeded to make incriminating statements. Acting on this information, Detective Winter and other officers applied for a warrant to search Rose’s residence, where they discovered ammunition, drug paraphernalia, and an unfinished AR-15 rifle. Later, while searching Rose’s clothing at the county jail, officers found a loaded pistol and a bag containing methamphetamine.
Rose was charged with possessing five grams or more of methamphetamine with intent to distribute and for unlawfully possessing a firearm as a felon. Rose moved to suppress the evidence from the traffic stop and the subsequent searches, arguing that the police lacked valid grounds to stop him in the first place and that the dog sniff unlawfully prolonged the stop. He also claimed that his statements to officers were obtained without a proper waiver of his Miranda rights.
When the case reached the district court, the court denied the defendant’s motion to suppress, finding that Detective Winter had probable cause to conduct the stop for the tint violation, that the canine sniff was properly conducted within the duration of the stop, and that Rose’s waiver of his Miranda rights was knowing and voluntary. As a result, Rose appealed to the Eighth Circuit, challenging the lower court’s denial of his motion to suppress the evidence discovered by law enforcement.
When law enforcement officers stop a vehicle, the Fourth Amendment demands that the stop be justified at its inception and conducted in a reasonable manner. Even a minor traffic violation can provide probable cause for a stop, regardless of the officer’s subjective motivations. Once a valid stop has been made, an officer may conduct a canine sniff of the vehicle, provided it does not unreasonably extend the duration of the stop beyond the time necessary to address the traffic violation. If the dog positively alerts on the vehicle, officers generally have probable cause to conduct a search. In considering Miranda issues, courts look to whether a defendant’s waiver of rights was voluntary, knowing, and intelligent. A waiver need not be signed; it can be inferred from the defendant’s actions and willingness to speak after being informed of those rights.
On appeal, the Eighth Circuit affirmed the district court’s denial of Rose’s motion to suppress, holding that Detective Winter’s initial traffic stop was grounded in probable cause, that the canine sniff occurred while the citation process was ongoing (thus not unlawfully extending the stop), and that Rose knowingly waived his Miranda rights.
The Circuit Court individually analyzed each of the claims presented. First, the Circuit explained that a straightforward traffic infraction, like unlawfully dark-tinted windows, establishes probable cause for a stop. In this case, Detective Winter had observed Rose’s heavily tinted windows before following him and watching him pull into a parking lot, so the Court concluded that the initial stop was reasonable regardless of the officer’s underlying suspicions about drug and firearm activity.
Unlock a 14-Day Free Trial of Our Weekly Training Series
Enter your email now to start exploring our Path of the Guardian training — no commitment required.
After confirming that the traffic stop began lawfully, the Court next addressed whether the canine sniff violated Rose’s Fourth Amendment rights by prolonging the stop. The Court explained the record showed that the officers remained occupied with legitimate tasks related to the stop—confirming Rose’s driving eligibility and writing citations—at the time Officer Roling arrived with his certified drug-detection dog. The dog’s alert occurred within minutes of the initial stop, and there was no evidence suggesting officers intentionally delayed issuing citations to accommodate the sniff. According to the Circuit, deploying a well-trained, certified dog around a lawfully stopped car during the ordinary course of a traffic stop did not offend the Fourth Amendment. Given the dog’s alerts, the officers had probable cause to search the vehicle, and discovering drugs and paraphernalia inside only strengthened that probable cause.
The Court then turned to Rose’s statements made after his arrest. Detective Winter read Rose his Miranda rights in the patrol car, and the officer reiterated them at the station before Rose made any incriminating remarks. The Court noted that a signed waiver is not required for a valid Miranda waiver; rather, courts look at whether the defendant understood his rights and spoke voluntarily. In light of Rose’s background and his straightforward, cooperative communication with officers, the Court found no indication that his will had been overborne or that any form of coercion was involved. Because Rose chose to speak after being advised of his rights, his statements were admissible. Concluding that the officers had acted lawfully at each stage, the Court affirmed the denial of Rose’s motion to suppress.
The Eighth Circuit’s decision in this case reinforces the critical principles that guide law enforcement in conducting traffic stops. As the Court explained, a clearly observed traffic violation, like excessively tinted windows, provides ample cause for a stop. The Court’s opinion explains that a certified canine sniff conducted within the natural duration of issuing citations does not amount to an unconstitutional extension of the stop. Further, even without a signed waiver, an individual’s knowing and voluntary decision to speak with officers after receiving Miranda warnings renders those statements admissible. For law enforcement, in your daily duties, remember the importance of articulating the basis for a stop, conducting canine deployments within the stop’s scope, and ensuring that any advisement of rights is clear, documented, and followed by voluntary cooperation.
References
[1] United States v. Rose, 124 F.4th 1101 (8th Cir. 2025).
