Puppy Doggy

So, on our way home from breakfast this morning we say this dog running across this VERY busy street and he nearly got hit ! ! !
So we turned around and followed him into a neighborhood and I got him to come to me so I could check for a tag - which there was none. A collar but no fucking tag ! He was SOAKED and dirty and, though was obviously well-fed, appeared to not have been to a vet in quite some time seeing as how bad his teeth looked.
Then a car pulled up - two women who'd turned around because they'd seen the dog on the busy street as well ! Good Samaritans ! YEAH !
So we knocked on a couple of doors - and no one knew who's dog it was - while J called the cops. The dog obviously belongs to SOMEONE.
I told J I want to check back in with the cops tomorrow to see if the doggy got safely home or if he had to be turned over to the pound.
If he does land in the pound I want to keep tabs on him and take him in if no one claims him.
He's an old dog...and VERY well behaved. I can't imagine he doesn't have someone who loves him and wants him back - but people can suck and if it turns out that his owner no longer wants him then we'll take him in (provided, of course, that he doesn't try to eat our cats or the bunny). And if we can't take him then I'll find him a no-kill shelter to take him in !
I really hope he does get home....I'm going to worry now until I have an answer.....