A K-9 Alert Doesn't Become Invalid Just Because No Drugs Are Found: U.S. 7th Cir. Affirms Firearm Conviction

United States v. Banks, No. 24-2227 (7th Cir. June 30, 2026)

TL;DR

The Seventh Circuit upheld a firearm conviction after rejecting multiple Fourth Amendment challenges arising from a traffic stop. The court held that officers had reasonable suspicion for the initial stop, did not unlawfully prolong the detention while the driver attempted to obtain updated insurance information, and lawfully searched the vehicle after a certified drug-detection dog alerted—even though no narcotics were ultimately discovered.

The Facts

Late one evening, an officer observed Deangelo Banks allegedly fail to activate his turn signal at least 100 feet before making a left turn, as required by Illinois law. After Banks parked in a nearby shopping center, marked patrol units initiated a traffic stop.

During the stop:

• Banks provided his driver's license.

• His insurance card was expired.

• Officers requested updated proof of insurance.

• Banks voluntarily exited his vehicle and called someone to obtain current insurance information.

• Approximately four minutes into the stop, another officer arrived with a certified narcotics detection dog.

• The dog conducted an exterior sniff and alerted to the vehicle.

• Officers searched the vehicle.

• No narcotics were found.

• Officers did discover a concealed handgun behind the center console.

Banks, a convicted felon, was charged with unlawful possession of the firearm. He sought suppression of the gun, arguing virtually every stage of the stop violated the Fourth Amendment.

The Issues

The Seventh Circuit considered four principal questions:

1. Was the initial traffic stop supported by reasonable suspicion?

2. Did officers unlawfully prolong the stop under Rodriguez v. United States?

3. Did the K-9 alert provide probable cause even though no drugs were located?

4. Was there sufficient evidence that Banks knowingly possessed the firearm?

   
   

The Holding

The Seventh Circuit answered yes to the government's position on every issue.

The traffic stop was lawful.

The stop was not unlawfully extended.

The certified K-9's alert established probable cause to search the vehicle.

The evidence was sufficient for the jury to conclude Banks constructively possessed the firearm.

The conviction was affirmed.

The Court's Reasoning

1. Weak testimony is not necessarily incredible testimony.

Banks argued the stopping officer could not accurately determine whether the turn signal violation actually occurred. The officer admitted he could not estimate exactly how far behind the vehicle he had been and made several imprecise estimates during testimony.

The district court acknowledged these weaknesses but nevertheless found the officer credible. The Seventh Circuit emphasized an important appellate principle:

Credibility determinations belong primarily to the trial judge.

Unless testimony is internally inconsistent, physically impossible, or contradicted by objective evidence, appellate courts generally will not overturn those findings. Here, the trial judge believed the officer's explanation that lighting conditions and familiarity with the roadway allowed him to observe the violation.

The reasonable suspicion finding therefore remained intact.

2. Rodriguez focuses on whether officers delayed the mission—not the stopwatch alone.

Banks next argued officers intentionally stalled so the K-9 unit could arrive.

The Seventh Circuit returned to the Supreme Court's framework in Rodriguez v. United States.

The question is not simply how long the stop lasted.

The real inquiry is whether officers added time to the stop beyond what was reasonably necessary to complete the traffic mission.

Here, officers were still attempting to verify Banks's insurance information because his insurance card had expired.

Importantly:

• Banks himself chose to call someone for updated insurance.

• He remained on the phone when the dog arrived.

• The K-9 sniff occurred while officers were still performing legitimate traffic-related tasks.

The court found no evidence officers delayed completion of the stop simply to wait for the dog.

That distinction mattered.

3. A "false alert" does not automatically eliminate probable cause.

Perhaps the most useful training point comes from Banks's argument that the dog must have been unreliable because officers found no narcotics.

The Seventh Circuit rejected that argument.

Relying heavily on Florida v. Harris, the court explained that probable cause is evaluated before the search—not after officers learn what they did or did not find.

A certified narcotics detection dog creates probable cause unless the defendant presents evidence undermining the dog's reliability.

The absence of drugs alone does not accomplish that.

The court noted several innocent explanations for why a trained dog may alert:

• residual odor from previously stored narcotics;

• narcotics recently removed;

• odor contamination;

• drugs hidden so effectively they were not discovered during the search.

Because Banks produced no evidence attacking the dog's certification, training, or handler interpretation, probable cause remained intact.

4. Constructive possession may be proven through circumstantial evidence.

Although Banks argued the gun was not his—and DNA testing did not identify him as a contributor—the court held sufficient circumstantial evidence supported the jury's verdict.

Among the evidence:

• the firearm was hidden inside his vehicle;

• his personal papers and cell phones were stored in the same area;

• he initially told officers everything inside the vehicle belonged to him;

• he later changed his story;

• recorded jail calls suggested he knew officers had gone "straight to where the lick was."

The Seventh Circuit concluded a rational jury could infer knowing possession even without fingerprints or DNA on the firearm.

Why This Matters for Law Enforcement

This opinion reinforces several recurring Fourth Amendment principles that officers should remember during roadside investigations:

• Document the continuing mission of the stop. If you are still verifying a driver's license, registration, insurance, warrants, or other legitimate traffic-related matters, document exactly what remains unfinished.

• Rodriguez is about delay—not simply elapsed time. Courts ask whether officers unnecessarily extended the stop, not whether a certain number of minutes passed.

• Certified K-9 alerts remain powerful evidence. A search does not become unconstitutional simply because no narcotics are ultimately recovered.

• Maintain thorough K-9 certification and training records. Although Banks offered no challenge to the dog's reliability, future defendants frequently do.

• Constructive possession cases often rely on the totality of circumstantial evidence. Ownership, control, inconsistent statements, location of the firearm, and other surrounding facts may collectively establish knowing possession.

  
  

Key Takeaway

United States v. Banks serves as another reminder that successful Fourth Amendment litigation often turns less on dramatic constitutional questions than on careful documentation of ordinary police work. Officers who can clearly articulate what investigative tasks remained underway during a traffic stop—and why those tasks had not yet concluded—place themselves in the strongest position to defend both the detention and any subsequent search. Likewise, a properly trained and certified narcotics detection dog continues to provide probable cause even when the search uncovers no drugs, so long as the dog's reliability has not been meaningfully called into question.

Disclaimer

This article is provided for educational and training purposes only. It is not legal advice and should not be relied upon as such. Court decisions are jurisdiction-specific, fact-dependent, and subject to change through future judicial decisions or legislative action. Officers should consult their agency policies, local prosecutors, and legal counsel when applying legal principles in the field.