The tasks that police dogs perform may vary, but typically include using scent to find suspects or missing persons, locating drugs and biting suspects to prevent them from fleeing or attacking a human officer, according to the North American Police Working Dog Association. They also act as a deterrent, since many suspects are intimidated by them and stop resisting when one is present, as noted by HowStuffWorks.com.
There are many different types of scent work, according to the North American Police Dog Working Association. Police dogs may be trained to clear buildings and smaller areas, as well as doing large area searches for a subject in an unknown location. They may also learn to track or trail subjects, which requires them to follow the scent the person left behind as he fled. Many dogs are trained to do multiple tasks.
The most common type of police dog is a narcotics dog, which is trained to find illegal substances, such as marijuana, as reported by HowStuffWorks.com. However, dogs may also be trained to find bombs and other explosive devices or to locate human remains. Arson dogs are used to investigate suspicious fires and can alert their handlers to the presence of accelerants.
Although most police dogs are trained to bite on command, they do not attack or attempt to injure the person seriously, according to HOME. Instead, the dogs bite the suspect and hold him in place until they get the command to let go.