The dogs do go home with their handlers at the end of their shift. The dogs live at home with their handlers. The living arrangements are unique to the handler, dog and family situation. I raised my dog Boomer from a 7 week old pup and he always lived in the house. He went out to his kennel when we had company. My current K9 Partner, Boru is a different dog altogether. He lives at my house, has a kennel and a yard to run in. He is not the dog you bring to the family picnic and has no interaction alone with my wife. He is either loose in the yard, or in a kennel if I am not home. If I was single and only had one dog, Boru could come int the house with me. He is not the dog I would have loose in the house with family members or guests. He is a working dog, not a pet.
It really depends on the dog and the situation. Police K-9's should be working dogs, first and foremost. Some can relax and home and be good family dogs, some can't. Doesn't make Boru a bad dog, he is an excellent Patrol / Narcotics dog. That is why I have him and what is needed from him.
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