Tweet
http://www.fff.org/comment/com1210t.asp
EXCERT
This returns to the key question: Does a detection dog's alert constitute probable cause?
In the 2005 case Illinois v. Caballes, the Supreme Court ruled that
a dog sniff conducted during a concededly lawful traffic stop that reveals no information other than the location of a substance that no individual has any right to possess does not violate the Fourth Amendment.
In other words, there can be no expectation of privacy regarding the possession of illegal substances, and without such an expectation the examination of a car is not a “search” under the Fourth Amendment. The dog's alert provided the necessary probable cause.
Thus, detection dogs have been called “probable cause on four legs.” But this description is accurate only if a dog's alerts are reliable. In his dissenting opinion on Caballes, Justice David Souter highlighted the issue of reliability. He wrote,
The infallible dog … is a creature of legal fiction.… 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.… [D]ogs in artificial testing situations return false positives anywhere from 12.5 to 60% of the time, depending on the length of the search.
The Clever Hans effect
Clever Hans was a horse owned by a German mathematics teacher named Wilhelm von Osten. Around the turn of the 20th century, Hans became an international sensation for his alleged ability to solve math problems, to spell words, and to perform other mental feats by stomping his hoof on the ground. In 1904, the New York Times ran an article entitled “Berlin's Wonderful Horse; He Can Do Almost Everything But Talk.” (PDF)
In 1907, a scientific investigation concluded that Hans was taking cues from the body language of von Osten and from audience reactions. There was no accusation of malfeasance on von Osten's part. The man was simply giving off involuntary signals, which the horse picked up. Since then the phenomenon of an animal performing based on involuntary cues from a human being has been labeled the “Clever Hans effect.”
In 2011, Lisa Lit, Julie B. Schweitzer, and Anita M. Oberbauer published a study entitled “Handler Beliefs Affect Scent Detection Dog Outcomes” in the scholarly journal Animal Cognition. The University of California, Davis researchers tested the Clever Hans effect on police dogs. Eighteen law enforcement handler-dog teams were involved in the experiment. All were trained and certified for detecting drugs, explosives, or both. The teams each performed two sets of searches in four rooms with five minutes allocated per search. In advance, the researchers told the handlers that each room could have as many as three target odors, and that some targets would be marked with red paper. They were not told that in fact no target would actually smell of drugs or explosives. In short, any alert from the dogs would be false.
The 144 searches conducted produced only 21 accurate detections; in other words, the dog gave no alert 21 times. The total number of false detections was 225. The highest rate of false alerts by far came in response to targets marked with red paper. The dogs were picking up the unconscious body language of their handlers.
In a Reason article (Feb. 21, 2011) entitled “The Mind of a Police Dog,” Radley Balko concluded,
In the process of domesticating dogs, we have bred into them a trait that tends to trump most others: a desire to please us — and toward that end, an ability to read us and a tendency to rely on us to help them solve their problems.
Conclusion
The use of detection dogs is increasing. One reason can be found in civil-forfeiture laws. Police departments are now able to confiscate vehicles, money, and other possessions that are used in the conduct of illegal activity. Attorney Darpana Sheth of the Institute for Justice, which filed an amicus brief in Florida v. Harris, commented, “Police dog handlers work in departments that are often funded through forfeiture funds, giving them a direct financial incentive to ‘police for profit’ rather than pursue the neutral administration of justice.”
There is also considerable incentive to use dogs for searches that could not otherwise be conducted under the law. Such searches are an end run around the need for warrants, which normally restricts police authority. As detection dogs become more common, however, the courts will be pushed to clarify the constitutional status of a sniff. Indeed, the need for clarity may be why the Supreme Court has agreed to hear these two detection-dog cases.
The implications for the Fourth Amendment are immense. For example, if the Jardines appeal is unsuccessful, there will be legal precedent for police to use detection dogs on the direct exterior of homes. The amicus brief filed by the Cato Institute on Jardines states, “this Court confronts whether government agents could walk a drug-sniffing dog to the front door of every home in America or similarly patrol lines at movie theaters, shopping mall entrances, and such without implicating the Fourth Amendment.” (PDF)
But the Supreme Court's findings are more likely to rest on circumstance than on constitutional principle. Jardines has the advantage of a person's reasonable expectation of privacy on his own property, within his own home. Harris is less likely to succeed.
Comment