November 20, 2012
The use of narcotics-detecting dogs is a well-established practice in American law enforcement operations. Trained dogs are routinely used in an attempt to discover the presence of drugs in a variety of settings, including motor vehicle stops, investigative detentions of individuals in public places, and scans of luggage at airports, train stations, or bus terminals. For the most part, the courts have sanctioned the use of trained dogs in the belief that their ability to detect drugs is so well developed and reliable that when they alert on a location, drugs will be discovered there. However, some recent studies have placed that confidence in the performance of trained dogs into question. Now, in a case that will be sure to have widespread repercussions for law enforcement, the U.S. Supreme Court has agreed to revisit the issue of the use of trained narcotics dogs in law enforcement.
In its first decision addressing searches by dogs, United States v. Place, 462 U.S. 696, 707 (1983), the Supreme Court held that the use of a "well-trained narcotics detection dog" to detect the odor of narcotics in luggage at an airport was not a search for purposes of the Fourth Amendment, and the Court strongly implied that the subsequent alert by the dog on the luggage—indicating that the dog did indeed smell narcotics—was by itself a sufficient basis to determine that there was probable cause to justify a search warrant to search the luggage. In reaching that conclusion, the Court determined that the dog sniff was "sui generis" in investigative procedures, meaning that the sniff was "much less intrusive than a typical search," while at the same time reliably informative regarding the contents of the luggage. Id. The Court ultimately held in Place, however, that despite being supported by reasonable suspicion, the detention of the luggage for 90 minutes while awaiting the arrival of the detection dog was too unreasonable to be justified as an investigative detention under Terry v. Ohio, 392 U.S 1 (1968), and therefore invalidated all that followed. The Court thus found that the evidence discovered in the luggage had to be suppressed.
Subsequently, in Illinois v. Caballes, 543 U.S. 405 (2005), the Court held that the use of a narcotics-detection dog to sniff around the exterior of a motorist's vehicle during an investigative stop was not a search, again because of the lack of a cognizable infringement on the motorist's Fourth Amendment rights. After the dog had alerted on the trunk of the vehicle, the police searched the trunk and discovered narcotics. In reinstating the ruling of the trial court that the search of the trunk was supported by probable cause, the Supreme Court necessarily concluded that the alert by the dog was itself enough to provide probable cause to search.
Justice Souter wrote a dissenting opinion in Caballes that questioned the reliability of narcotics dogs and thus questioned the underlying justification for the Place rule. Souter argued that there was little reason to believe that a special rule should be applied to dog sniffs, as the unique reliability of trained dogs was simply not shown by empirical findings:
At the heart both of Place and the Court's opinion today is the proposition that sniffs by a trained dog are sui generis because a reaction by the dog in going alert is a response to nothing but the presence of contraband. . . .
The infallible dog, however, is a creature of legal fiction. Although the Supreme Court of Illinois did not get into the sniffing averages of drug dogs, their supposed infallibility is belied by judicial opinions describing well‑trained animals sniffing and alerting with less than perfect accuracy, whether owing to errors by their handlers, the limitations of the dogs themselves, or even the pervasive contamination of currency by cocaine.
Id. at 411-12 (Souter, J., dissenting) (footnote omitted).
The concerns expressed by Justice Souter have not seemed to trouble many lower courts, as the prevailing view in both federal and state courts has long been simply to view an alert by a trained narcotics dog as proof that narcotics are present. This view is represented by the court in United States v. Sundby, 186 F.3d 873 (8th Cir. 1999), which stated that "[a] dog's positive indication alone is enough to establish probable cause for the presence of a controlled substance if the dog is reliable. To establish the dog's reliability, the affidavit need only state the dog has been trained and certified to detect drugs." Id. at 876. Some courts have even refused to permit discovery by the defendant into the handler's training and experience with the particular dog or the dog's training and track record in the field. See, e.g., State v. Nguyen, 157 Ohio App. 3d 482, 2004-Ohio-2879, 811 N.E.2d 1180 (collecting similar cases).
There have been a few lower courts that have taken a more cautious view, however. Recently, the court in Harris v. State, 71 So. 3d 756 (Fla. 2011), noting a conflict in its state courts of appeal on the issue of alerts by trained narcotics dogs, squarely held that the fact that a drug‑detection dog has been trained and certified to detect narcotics, standing alone, is not sufficient to demonstrate the reliability of the dog for purposes of determining probable cause for a search. The facts before the court in Harris showed that law enforcement officers had stopped the defendant's truck because it had an expired license tag. Based on their belief that the defendant appeared to be extremely nervous, had an open beer in the truck, and refused consent to search the truck, the officers deployed a narcotics-sniffing dog to walk around the truck. After the dog alerted on the driver's door, the officers opened the door and searched the interior of the passenger compartment, locating a quantity of chemicals that were precursors of methamphetamine.
The defendant moved to suppress the evidence, arguing that it was the product of an illegal search. The court granted the defendant's discovery motion to obtain the training and certification records pertaining to the dog, and those records showed that while the dog's handler rated the dog's performance in training sessions with vehicles as "satisfactory" 100% of the time, the handler did not explain whether a satisfactory performance included any alerts to vehicles where drugs were not placed. With regard to the dog's performance in the field, the officer testified that he deployed the dog to sniff vehicles about five times each month but that he kept records of the field performance only when he made an arrest. The officer acknowledged that he did not keep records of the dog's alerts in the field when no contraband was found. Thus, the court found, it was impossible to determine what percentage of the time the dog alerted and no contraband was found following a warrantless search of a vehicle. Significantly, the defendant himself testified that his vehicle had been the subject of a sniff by the same dog the month before and that the dog had alerted in the same way but that the police had found no contraband in the truck and had allowed the defendant to go on his way. The officer responded to this testimony by giving his opinion that the dog was alerting to a residual odor of methamphetamine on the door handle, but he could not offer an opinion with regard to how long ago someone who had handled the drug would have had to touch the handle in order to trigger an alert.
On the basis of these facts, the court held that the State did not provide a sufficient basis to find that there had been probable cause to search the defendant's vehicle. Noting first that the determination of probable cause was subject to a totality-of-the-circumstances test, the court found that
Because the dog cannot be cross‑examined like a police officer whose observations at the scene may provide the basis for probable cause, the trial court must be able to assess the dog's reliability by evaluating the dog's training, certification, and performance, as well as the training and experience of the dog's handler. Similar to situations where probable cause to search is based on the information provided by informants, the trial court must be able to evaluate the reliability of the dog based on a totality of circumstances. . . .
Like the informant whose information forms the basis for probable cause, where the dog's alert is the linchpin of the probable cause analysis, such as in this case, the reliability of the dog to alert to illegal substances within the vehicle is crucial to determining whether probable cause exists. If a dog is not a reliable detector of drugs, the dog's alert in a particular case, by itself, does not indicate that drugs are probably present in the vehicle. In fact, if the dog's ability to alert to the presence of illegal substances in the vehicle is questionable, the danger is that individuals will be subjected to searches of their vehicles and their persons without probable cause. Conversely, if a dog is a reliable detector of drugs, the dog's alert in a particular case can indicate that drugs are probably present in the vehicle. In those circumstances, the drug‑detection dog's alert will indicate to the officer that there is a "fair probability that contraband" will be found. Gates, 462 U.S. at 238, 103 S.Ct. 2317. Thus, to determine whether the officer has a reasonable basis for concluding that the dog's alert indicates a fair probability that contraband will be found, the trial court must be able to adequately make an objective evaluation of the reliability of the dog.
Id. at 767.
The court thus concluded that "when a dog alerts, the fact that the dog has been trained and certified is simply not enough to establish probable cause to search the interior of the vehicle and the person." Id. Noting that there was no state or national uniform standard with regard to training or certification for drug-detection dogs, the court decided that in the absence of such a standard, the reliability of a dog could not be established by demonstrating only that the canine is trained and certified. Therefore, the court found that whether a dog has been sufficiently trained and certified must be evaluated on a case‑by‑case basis. The court further recognized a potential problem in assessing reliability related to handler cuing, as even well-trained dogs could respond to subconscious cues from their handlers. For this reason, the court determined that a critical factor in determining reliability is the record of false positive alerts made by the dog.