Supreme Court: No set requirements for drug-sniffing dogs to show probable cause
For a drug-sniffing dog's detection to show probable cause for a search, law enforcement doesn't need to fulfill any particular requirements that prove the dog's ability, the Supreme Court ruled unanimously on Feb. 19.
To find probable cause, the Supreme Court has consistently rejected "rigid rules, bright-line tests, and mechanistic inquiries in favor of a more flexible, all-things-considered approach," Justice Elena Kagan wrote in the opinion. The ruling overturned a Florida Supreme Court decision.
In 2006, a K-9 officer pulled over Clayton Harris for an expired license plate. Harris had an open beer can in one of his cup holders and declined to consent to a search of his truck. The officer walked his dog, trained to detect narcotics, around the truck, and the dog signaled that he smelled drugs.
The officer's search didn't find any drugs the dog was trained to detect, but it did turn up 200 pseudoephedrine pills, a bottle of hydrochloric acid, iodine crystals and other ingredients to make methamphetamine. Harris admitted that regularly cooked and used the drug. Later, while out on bail, Harris was pulled over for a broken brake light--by the same officer and dog. The dog again signaled that he detected drugs, but this time the officer's search found nothing.
The Florida Supreme Court held that the officer lacked probable cause to search the truck. It said the state needed to show evidence of the dog's performance and training history, along with evidence of the officer's experience and training.
The Supreme Court disagreed. Justice Kagan wrote that those requirements constitute "a strict evidentiary checklist, whose every item the State must tick off." Probable cause should instead be based on "the totality of the circumstances," she said.
She also criticized the particular requirements. If the state must show evidence of a dog's performance history, "One wonders how the court would apply its test to a rookie dog," she wrote.
Plus, drug-sniffing dogs' performance histories would fail to account for false negatives and mistakenly record false positives, Kagan noted. If a dog fails to detect drugs, then a search probably won't follow, so the officer won't find out that the dog didn't detect the drugs. The dog might also detect drugs that the officer can't find if they're well-hidden or there's only a small quantity, and the officer would record that instance as a false positive.
Better evidence of a dog's detection ability would come from a training or certification program, where it's known whether there are drugs present or not in tests, Kagan said.
A defendant can make the case that a drug-sniffing dog has underperformed in training or certification, or that those programs were flawed, but Kagan said there shouldn't be "an inflexible set of evidentiary requirements" for the state to show probable cause.
In this case, the officer had completed a 160-hour course in narcotics detection, and the dog had done a similar 120-hour course, each in 2004. The two together did a 40-hour refresher course in 2005. At trial, the officer said his dog probably detected the odor of meth on the door handle, which Harris, a habitual user, had likely left there.
- download the Supreme Court opinion in Florida v. Harris (.pdf)