Would you call the police ....

Of course, I'd call them. It's our civic duty to report these incidents. You can do so anonymously, if you feel threatened.

I don't believe it requires involving the police. You could call the town's business office or county roads department to inform them that the sign needs to be replaced and leave it at that.

Absolutely

Well, technically I wouldn't have to. I live on a MAJOR street and there is a stop sign literally 10 feet from my front door so if that happened the police would be there before they could arrange a tow. But if I lived elsewhere, where the police weren't always going by my front door:

My first instinct was "no" I wouldn't call, it's just a stop sign and their car is disabled so they won't be driving anymore. But then I thought what if it was drugs or alcohol or just stupidity i.e. young driver with a bunch of friends, that caused the crash. Even if they had a friend pick them up, they might end up on the road again in a different car and would I want them driving again that night? The answer is probably no so maybe I would call the police. I suppose it might come down to how they are acting while waiting for the tow and a ride.

Well, the driver was quite upset and kicking the car. I did call, mainly because the stop sign needs replacing - I never thought of calling the road dept - I'll do that, too. I just thought it was odd she said not to call, MYOB!

Yes I would call the police, and the saying "it's just a Stop Sign" is ridiculous! The sign being knocked down could cause someone to get killed!

Maybe your neighbor knows who the kids are or is related to them!

You already know the answer to that question. Yes.

Of course I would call.

What if the driver was injured, or worse yet, drunk?

That's right! Any time a stop sign is down is a potential emergency. I'd call for that reason alone.

I lived on a busy corner downtown Sacramento and anytime I heard an accident outside I would call.