How sad, about the young man who died. I'm so sorry. I will say that while it's easy to think of things one would have / could have / should have done differently after any bad event, really there are no guarantees that a different plan would have led to a better outcome (per your example also of me taking my DS in the car with me versus having an accident at home -- either could have happened).
Crime is definitely down in my immediate neck of the woods. I can't find statistics online comparing my childhood to now, but I'd guess it's down from then. Over the last 10 years in my county, the violent crime rate per 100,000 has dropped from 371 to 273. Rape is up -- 11 to 20, though I'd guess this may be partly reporting (maybe not). Assault is down from 222 to 97.
Obviously other areas will have different experiences and of course plenty of folks aren't raising their children in the same area where they grew up so that makes comparisons like mine irrelevant for them.
We too have problems with speeders, etc., don't get me wrong ... I am definitely not advocating throwing caution to the winds but I also want to raise my DS to be an active, capable, and independent person. Actually I think I will start another thread on that subject which I think is another way to approach the same (general) issue.