Glossary
Police K-9
A dog trained to assist law enforcement, usually in tracking, apprehending suspects and detecting drugs or explosives, working with one handler.
Also called: K-9, K9, police dog, law enforcement dog, patrol dog, K-9 unit, canine officer
A police K-9 is a dog that works with a law enforcement officer. The term K-9 is a play on the word canine. Dogs may be trained for patrol work, tracking suspects, searching buildings, apprehending people, or detecting drugs, explosives or other items by scent. Many are dual purpose, trained for both patrol and detection.
Common breeds are the German Shepherd Dog, the Belgian Malinois, the Labrador Retriever and the Bloodhound, and many come from European working lines. A dog usually lives with its handler and trains throughout its career. The relationship between handler and dog is central.
A K-9 is a certified working animal and may have legal protections, such as penalties for harming one. It is separate from a service dog, which helps a person with a disability, and from a search and rescue dog dog, which finds missing people. Policies on use of force differ by agency.
Last reviewed November 8, 2026