Here's a problem to chew over:

[zipplewrath]

2. That's a boat load of assumption there

But accepting all of your assumptions for a moment, back then a 17 year would have more than likely been treated as a juvinile. Not sure where they were, but both were probably too young to be drinking where they were. So they'd both probably get some sort of "diminished capacity" defense. At this point, the 62 year old would be liable for vehicular manslaughter, probably doing some fraction of a year in prison and followed by a rather length parole. The 19 year old would have to be identified as part of any deal, and that person would get some sort of accessory charge, and maybe a "contributing to the deliquency".

If I could decide, I'd struggle mightily. I'm not a big fan of our current judicial system, ESPECIALLY in the category of incarceration and punishment. So I'd be lenient on the front end, with the milder consequences lasting pretty much for the rest of his life.