Who do you call?

WH is my neighbours' son. Nice polite boy, always says hi, just started college.

One night, my parents told me an unmarked police car had been seen next door. 3 cops came out, questioned WH at length after which got into the car with them and drove off. 1 cop drove away WH's jeep.

He did not return the next morning. In fact, nobody from my neighbours' house returned next morning. I usually see WH's dad as I return from my morning run but his car wasn't even in the driveway. I usually see his sister when I go to work, but she wasn't there either. They emerged the following day visibly affected - solemn and reluctant to make conversation.

Over the course of the week, we began to speculate and my parents' conclusion was it might be a car accident, maybe even a hit-and-run. WH is a nice enough boy, but he kept company with some rowdy types (one time, one of them parked his Evo 7 right across our driveway and when politely asked to move it waved us off with a flippant "I'm not gonna be here long." before going into the house). My folks thought whatever happened might not have been WH's fault, but perhaps his friends had borrowed his car and something happened.

I began to wonder all sorts of things:
Was he in custody?
Were they getting a lawyer?
If he was in the wrong could they plea-bargain like you did in the movies?
Who would I call?
Should we think about getting a family lawyer for things like this?
How do I ask how he's doing without embarrassing my neighbours? Or myself?

Another thing I thought about was had I come home and seen the cops questioning him, would I have stepped in and asked if he needed help? Or would I have slinked into the house and watched from the window?

A week later, WH came home. Thinner, but otherwise himself. And after that, things quickly returned to normal.
I never asked him what happened.
I still don't have a lawyer.