Dogs bred and trained to aid and assist police officers, known as K9s, are often held out to the public as a soft, likeable law enforcement mascot, even serving as the basis for characters in children’s cartoons. The truth, however, is much more complex.
Police K9s have many applications. They are trained to sniff out and detect drugs and explosives. They are also used to apprehend suspects.
Many have long assumed that K9s respond honestly and accurately when they detect the scent of drugs or explosives. However, studies have shown that the bias of the K9’s human handler can influence the dog’s behavior. One study led handlers to believe they were simply looking for target scents that were hidden, when in fact there were no scents to be found. Nevertheless, the K9s alerted to “scents” that were not present, leading the study’s author to conclude that it was the behavior of the handlers, not the capability of the K9, which caused the false-positives. Another study randomized the presence of target scents – they were present in some scenarios and absent in others – and again found K9s responding to false positives, leading to a similar conclusion: handler behavior can affect the K9’s.
The use of K9s to apprehend suspects is rationalized as being a utilization of a lesser degree of force that can prevent harm to Police Officers and civilians. When the K9 is merely an intimidating force, and just the threat of its deployment is sufficient to gain the compliance of a suspect, that premise is probably true. But the use of K9s to bite suspects is subject to the same Fourth Amendment limitations that apply to other uses of force. Depending on the specific facts of the case, the use of a K9 can not only cause injuries, but may result in a civil rights violation.
Most K9s are trained to “bite and hold” a suspect. The misleadingly named technique often results in serious injuries to the suspect, and in some cases has been utilized under circumstances where the use of any degree of physical force is questionable. A recent report by NPR (here is a link – which includes a moderately graphic video) highlights the violent nature of K9 apprehensions. Indeed, that the very concept of the bite and hold technique is a euphemism has been confirmed in scientific studies, finding that injuries caused by K9s are often much more serious than those caused by domestic pets. That conclusion is not surprising. As law professor Seth Stoughton, quoted in the NPR report, observes, when the dog is biting a suspect, the suspect is focused on the pain of the bite. As a result, they may kick or flail, only to be viewed as resisting arrest, all prolonging the duration, and severity, of the bite, which only ends at the command of the handler.