Police dog (K9)

A police dog, also known as a K-9 or K9 (a homophone for dog), is a dog specially trained to assist law enforcement personnel. Dogs have been used in law enforcement since the Middle Ages. The most commonly used breeds are the German Shepherd and Belgian Malinois, but there are many other breeds that have some unique talents. For example, basset hounds, bloodhounds, and Labrador retrievers are known for their tracking, tracking, and detection skills. Police K-9s are widely used as law enforcement throughout the United States, and typically serve on the force for 6 to 9 years. In many countries, it is a criminal offense to intentionally injure or kill a police dog.
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Police departments require the dog to pass basic obedience training first. Dogs must be able to respond to their handler's commands and comply with them without hesitation for proper control.

There are two common police K-9 classifications:

Periodicity: These dogs are used for patrol duties (protecting officers, arresting suspects, clearing an area or building, and security in sensitive or controlled areas).
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Disclosure: These dogs are used to find drugs or explosives. Note that it is either one or the other.

Law enforcement dogs are trained to be either “single-purpose” or “dual-purpose” K9s.

Single-purpose dogs are primarily used for either patrol or detection duties. We also have single-purpose K9 devices that are only used to track or locate missing persons or discover bodies.
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Dual-purpose dogs are trained to combine these duties into a single K9 dog. In the United States, when a drug car K-9 signals to its driver that she detected the odor of drugs by searching the perimeter of the vehicle, the officer has reasonable cause to search the entire vehicle without a warrant.