By Russ Belville
One of the favorite tools of law enforcement officers looking to bust cannabis consumers is the K-9 unit (or as George Clinton once called ‘em, the “dope dog”). These dogs are highly trained to use their super sense of smell to detect narcotics and explosives. Paired with a handler, they are often called in to search suspect vehicles in traffic stops and signal, or “alert” when contraband is detected.
Researchers at UC Davis decided to put the K-9s to the test and it didn’t turn out well for the cop’s best friend. These detection dogs, whose alerts are used to justify search warrants and convict cannabis consumers, gave false alerts more than 200 times.
The study, published in the January issue of the journal Animal Cognition, found that detection-dog teams erroneously “alerted,” or identified a scent, when there was no scent present more than 200 times — particularly when the handler believed that there was scent present.
“It isn’t just about how sensitive a dog’s nose is or how well-trained a dog is,” says Lisa Lit, a postdoctoral fellow in the Department of Neurology and the study’s lead author. “There are cognitive factors affecting the interaction between a dog and a handler that can impact the dog’s performance.”
The researchers took 18 drug dog teams to a church, where it is likely no drugs or explosives had ever been placed in the past. The cops were told there might be up to three target scents in any one of four rooms. If they saw a piece of red construction paper in the room, that indicated where a target scent was placed.
The first room was left untouched. The second room had a piece of red construction paper on a cabinet. The third room had two sausages and two tennis balls placed as decoys. The fourth room had the decoy scents and the red paper. However, none of the rooms had any drugs or explosives.
There shouldn’t have been any alerts, but, in fact, handlers indicated their dog had alerted in every room. There were more alerts in rooms with red paper (which piques the cop’s interest) and no corresponding increase in rooms with sausages and tennis balls (which would pique a dog’s interest).
In other words, at best, dogs are responding to the subtle non-verbal cues of their masters to find drugs or explosives where the human thinks there should be drugs or explosives. The cop suspects you have pot so his body language makes the dog alert. At worst, the cop is purposefully cuing his dog to alert when he wants a handy excuse to violate your 4th Amendment rights.