Supreme Court Takes on Drug-Sniffing Dogs

A cop with an accommodating canine can search whatever he wants.

Our dog, a Maltese/Yorkshire terrier mix named Lana, knows one trick: She sits on command. Sometimes this will get her a peanut, but it does not really do anything for me.

When Aldo and Franky sit, by contrast, they accomplish something important for their police handlers, signaling the presence of illegal drugs and justifying searches that would otherwise be prohibited by the Fourth Amendment. Two cases the Supreme Court heard last week offer an opportunity to impose long overdue restraints on this amazing ability to transform a cop's hunch into probable cause, which is based on serious misconceptions about the meaning of a police dog's "alert."

Aldo, a German shepherd, was riding with Officer William Wheetley of the Liberty County, Florida, sheriff 's office on June 24, 2006, when Wheetley pulled over a pickup truck driven by Clayton Harris because of an expired tag. Harris seemed nervous to Wheetley, who later said he was shaking, restless, and breathing rapidly.

Wheetley asked for permission to search the truck, and Harris said no. But thanks to Aldo and the Supreme Court, Wheetley did not have to stop there. Seven years ago, the Court declared that "the use of a well-trained narcotics-detection dog…during a lawful traffic stop generally does not implicate legitimate privacy interests." So Wheetley was free to walk Aldo around the truck.

According to Wheetley, Aldo got excited and sat down in front of the driver's side door handle, thereby allowing him to search the vehicle. Wheetley did not find any substances that Aldo is trained to detect, but he did find 200 pseudoephedrine tablets, along with other chemicals and supplies used to make methamphetamine.

About two months later, Wheetley stopped Harris again, this time ostensibly because of a malfunctioning brake light, and went through the same ritual. According to Wheetley, Aldo alerted to the same door handle, but once again there were no drugs in the vehicle.

Wheetley speculated that on both occasions Aldo smelled traces of meth transferred from Harris' hand, which might be true (although a smell on the outside of a vehicle does not necessarily originate with its owner). But perhaps Wheetley, keen to confirm his suspicions about Harris, misinterpreted Aldo's behavior or subconsciously cued him to alert.

Such factors help explain why searches triggered by drug-sniffing dogs so often fail to find the substances supposedly detected by the animals' keen noses: 56 percent of the time in a 2011 Chicago Tribune analysis, 74 percent in a 2006 Australian study, 96 percent in a 1984 Florida roadblock operation. Yet the state of Florida insists Aldo's track record is irrelevant in determining whether Wheetley's search of Harris' truck was legally justified. It says courts should simply accept police assurances that a dog is "well-trained."

Amazingly, the Supreme Court last week seemed inclined to accept that argument, which gives cops with sufficiently accommodating dogs the ability to search at will. The justices were more troubled by the implications of that dog license in the case involving Franky, a Labrador retriever whose alert to the front door of a Dade County, Florida, house was the basis for a search warrant that led to Joelis Jardines' 2006 arrest for growing marijuana.

Even Justice Antonin Scalia, who in the Harris case ridiculed the notion that cops might prefer dogs who let them search whatever and whenever they want, seemed persuaded that police should have a warrant before bringing canine detectives to your doorstep for the purpose of uncovering information about what is happening inside your home. Otherwise, Justice Ruth Bader Ginsburg noted, police "could take a dog and go [up to] every house on the street, every apartment in the building."

If you think you have nothing to fear from such olfactory dragnets because you have not broken the law, you should take a closer look at when and why dog alerts lead to fruitless searches of innocent people. So should the Supreme Court.