The appropriate answer is never, dogs really shouldn't be off-leash for their own safety. Dogs can be stolen, injured, or can run off.
I do however, let Aztec out off leash. Both at the park, and in my front yard. This not a thing that happens all that often - as I do have a very large yard that has a 6ft privacy fence. He tends to stay closer to me when he is off leash than when he is on a leash. One exception was this past weekend, when I went to find my mom and saw Aztec laying in the front yard. There he was sleeping, completely alone...apparently he had wandered back out there when she had gone to the backyard. There was also a time where he slipped out of the house while we were leaving, and sat on the far side of our garage until we returned. I would never, ever in my life let Laika off her leash or she would be gone within seconds.
I do however, let Aztec out off leash. Both at the park, and in my front yard. This not a thing that happens all that often - as I do have a very large yard that has a 6ft privacy fence. He tends to stay closer to me when he is off leash than when he is on a leash. One exception was this past weekend, when I went to find my mom and saw Aztec laying in the front yard. There he was sleeping, completely alone...apparently he had wandered back out there when she had gone to the backyard. There was also a time where he slipped out of the house while we were leaving, and sat on the far side of our garage until we returned. I would never, ever in my life let Laika off her leash or she would be gone within seconds.

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