The Observer Effect and Police Dogs

Most people know that our pets, especially dogs, like to please us. Well, it goes for police dogs, too.

My confusion about what was going on in Harper's head reflects a common misconception that is also apparent in the ways dogs are used in criminal investigations. When we think dogs are using their well-honed noses to sniff out drugs or criminal suspects, they may actually be displaying a more recently evolved trait: an urgent desire to please their masters, coupled with the ability to read their cues.

Several studies and tests have shown that drug-sniffing dogs, scent hounds, and even explosive-detecting dogs are not nearly as accurate as they have been portrayed in court. A recent Chicago Tribune survey of traffic stops by suburban police departments from 2007 to 2009, for example, found that searches turned up contraband in just 44 percent of the cases where police dogs alerted to the presence of narcotics. (An alert is a signal, such as barking or sitting, that dogs are trained to display when they detect the target scent.) In stops involving Hispanic drivers, the dogs' success rate was just 27 percent. The two largest departments the Tribune surveyed—the Chicago Police Department and the Illinois State Police—said they don't even keep track of such information.

But don't blame the dogs; their noses work fine. In fact, the Pentagon’s Defense Advanced Research Projects Agency recently conceded, after 12 years and millions of dollars of research, that the canine snout, fine-tuned by millions of years of evolution, is still far more sensitive and reliable than any technology man has been able to muster when it comes to detecting explosives in places such as Iraq and Afghanistan.

The problem is our confusion about when dogs are picking up a scent and when they are responding to cues from their handlers.

This is similar to a well-known problem in physics - the observer effect - where a person observing an event has an impact on the event and skews it. Obviously this is slightly different in that the dog's handler can safely observe the dog in action; they just have to be careful not to give the dog false clues so that the dog ends up simply trying to please its master rather than do its job.

It seems like this could have a bearing on parenting, as well. When raising children we must be careful that they do not end up doing something just to gain our approval. They must learn to do the right thing even when it is harder or they worry it might mean our disapproval somehow (if, for example, they try to accomplish a task but fail).