The Hat Squad, on CBS
IMDb; TV Tango; Wikipedia

I'm afraid I don't remember much about this show except that I thought it was pretty cool. James Tolkan played this cop who was retired I think, and I believe he used to be part of a group of detectives called the Hat Squad. And he had adopted three boys who were now grown up and had become cops who were themselves a new generation of the Hat Squad. And they wore dusters and fedoras and it was a really cool look. Seriously. And, y'know, it was just a decent police detective family drama type show which was cool and didn't last long (only 11 episodes; 2 more unaired). I'd love to see it again someday.

...Um, but I may have been mistaken about the coats they wore being dusters, I'm not sure. They definitely wore fedoras, though.