A police dog, or K-9, is a dog trained to assist police and other law enforcement personnel. The word K-9 (key-nine) is synonymous with the Latin word canine, meaning dog. The most commonly used dog breed for this purpose is the German shepherd.
In most jurisdictions, the deliberate killing or injury of a police dog is a felony and the perpetrator receives a heavier penalty than torture to a normal animal. While some security forces use steel vest police dogs, some have uniforms and badges for dogs on duty.
Police dogs can be used to catch criminals and prevent the caught criminal from escaping. Apart from that, police dogs are used for:
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