CSSA Magazine Article – U.S. Supreme Court Rules In Favor Of Drug Sniffing Police Dogs


By: Martin J. Mayer, General Counsel

California Peace Officers’ Association

The United States Supreme Court, on February 19, 2013, in the case of Florida v. Harris, unanimously held that it was not unreasonable for an officer to search a vehicle after his drug sniffing dog alerted at a truck during a routine traffic stop.

William Wheetley is a K–9 Officer in the Liberty County, Florida Sheriff’s Office. “On June 24, 2006, he was on a routine patrol with Aldo, a German shepherd trained to detect certain narcotics (methamphetamine, marijuana, cocaine, heroin, and ecstasy). Wheetley pulled over re­spondent Clayton Harris’s truck because it had an expired license plate. On approaching the driver’s-side door, Wheetley saw that Harris was “visibly nervous,” unable to sit still, shaking, and breathing rapidly. Wheetley also noticed an open can of beer in the truck’s cup holder.”

“Wheetley asked Harris for consent to search the truck, but Harris refused. At that point, Wheetley retrieved Aldo from the patrol car and walked him around Harris’s truck for a “free air sniff.” When Aldo alerted at the door of the truck, the officer believed he had probable cause to conduct a search, which resulted in finding material used to manufacture methamphetamine.

The State charged Harris with possessing pseudoephedrine for use in manu­facturing methamphetamine.  Harris moved to suppress the evidence found in his truck on the ground that Aldo’s alert had not given Wheetley probable cause for a search.  When the trial court ruled that probable cause existed, he pled no contest and, thereafter, challenged the court’s ruling regarding the probable cause.

An appellate court upheld the lower court, but the Florida Supreme Court reversed, stating that to demonstrate a dogs reliability, “the State must present . . . the dog’s training and certification records, an explanation of the meaning of the particular training and certification, field perfor­mance records (including any unverified alerts), and evidence concerning the experience and training of the officer handling the dog, as well as any other objective evidence known to the officer about the dog’s reliability.”

The Florida Supreme Court “stressed the need for “evidence of the dog’s performance history,” including records showing, “how often the dog has alerted in the field without illegal contraband having been found.”  The U.S. Supreme Court granted certiorari and reviewed the issue of whether there was a violation of the 4th Amendment’s prohibition on unreasonable searches and seizures.

Probable Cause for the Search

The primary issue on which the United States Supreme Court focused was whether “prior hits and misses” by the dog needed to be documented in order to establish probable cause for the search.  The Court noted that the “Florida Supreme Court held that the State must in every case present an exhaustive set of records, including a log of the dog’s performance in the field, to establish the dog’s reliability. We think that demand inconsistent with the “flexible, common-sense standard” of probable cause.”

“A police officer has probable cause to conduct a search when “the facts available to [him] would ‘warrant a [person] of reasonable caution in the belief ’” that contraband or evidence of a crime is present. The test for probable cause is not reducible to “precise definition or quantification.”

The Court further stated that “[i]n evaluating whether the State has met this practical and common-sensical standard, we have consistently looked to the totality of the circumstances.  We have rejected rigid rules, bright-line tests, and mechanistic inquiries in favor of a more flexible, all-things-considered approach.”

The Court rejected the demand by the Florida Supreme Court for an “evidentiary checklist” of documentation in order to establish reliability of a drug sniffing dog.  “[A] finding of a drug-detection dog’s reliability cannot depend on the State’s satisfaction of multiple, independent eviden­tiary requirements. No more for dogs than for human informants is such an inflexible checklist the way to prove reliability, and thus establish probable cause.”

Training and Testing of the Dog

The Supreme Court does hold that there is a need to prove a dog’s reliability, but it strongly disagreed with the need to show “hits and misses” in the field.

“The better measure of a dog’s reliability thus comes away from the field, in controlled testing environments.For that reason, evidence of a dog’s satisfactory performance in a certification or training program can itself provide sufficient reason to trust his alert.  If a bona fide organization has certified a dog after testing his reliability in a controlled setting, a court can presume (subject to any conflicting evidence offered) that the dog’s alert provides probable cause to search.”

The Court also noted that law enforcement, itself, would want reliable dogs and want to ensure reliability of the animal.  “[L]aw enforcement units have their own strong incentive to use effective training and certification programs, because only accurate drug-detection dogs enable officers to locate contraband without incurring unnecessary risks or wasting limited time and resources.”

Challenging the Dog’s Reliability

Nonetheless, and obviously, the Court stated that a “defendant, however, must have an opportunity to challenge such evidence of a dog’s reliability, whether by cross-examining the testifying officer or by introducing his own fact or expert witnesses. The defendant, for example, may contest the adequacy of a certification or training program, perhaps asserting that its standards are too lax or its methods faulty.”

Furthermore, “even assuming a dog is generally reliable, circumstances surrounding a particular alert may undermine the case for probable cause—if, say, the officer cued the dog (consciously or not), or if the team was working under un-familiar conditions.”

The Court stated that a probable cause hearing regarding a drug sniffing dog should be conducted as any probable cause hearing would be conducted.  “The question—similar to every inquiry into probable cause—is whether all the facts surrounding a dog’s alert, viewed through the lens of common sense, would make a reasonably prudent person think that a search would reveal contraband or evidence of a crime. A sniff is up to snuff when it meets that test.”


“Because training records established Aldo’s reliability in detecting drugs, and Harris failed to undermine that showing, we agree with the trial court that Wheetley had probable cause to search Harris’s truck. We accordingly reverse the judgment of the Florida Supreme Court.”

And, according to this decision, once probable cause exists for the search, whatever contraband is discovered, even when it could not have been detected by the dog as was the situation in this case, the evidence can be used for prosecution.

That is true because “if the dog alerts to a car in which the officer finds no narcotics, the dog may not have made a mistake at all. The dog may have detected substances that were too well hidden or present in quantities too small for the officer to locate. Or the dog may have smelled the residual odor of drugs previously in the vehicle or on the driver’s person. Field data thus may markedly overstate a dog’s real false positives. By contrast, those inaccuracies—in either direction—do not taint records of a dog’s performance in standard training and certification settings.”

As such, it is not necessary for law enforcement to produce detailed documentation, indicating all of the “hits and misses” of a drug detecting dog’s activity in the field, in order to prove the dog’s reliability.  But it will be necessary to provide documentation that the dog has been trained, certified, and tested for reliability.

Martin J. Mayer is a name partner with the public sector law firm of JONES & MAYER which represents law enforcement agencies throughout the state.  Mr. Mayer has served as general counsel to CPOA for over 25 years.

[Originally published in the California Peace Officers’ Association Magazine, March 5, 2013]