A no-kill shelter is just that. They keep the animals until someone adopts/rescues them.
And one can't assume that the previous owner dumped the dog or mistreated it. Many dogs run off because they just wanna feel the wind in their ears.
Coupla summers ago, ours was in the back yard for a 10 minute potty break and was not there when I called for him to come back in.
The idiot TWC dudes had left the gate open on the far end of the yard... after I had asked them to make sure they latched it when they left.
After putting it on our neighborhood email listserv and getting no results for a coupla hours, a neighbor three houses down walked over and showed me a Facebook post he had received from some friends four blocks away. He recognized him as ours and his friends' post said they had him in their back yard. He called them on his phone to make sure they were home and I went to get him.
After that, I always check behind anyone who has to go in our backyard before letting him out because that taught me that it's not smart to trust them to be conscientious.
Newbie: