Let me give you one of the saddest stories I know. The decedent was a work colleague, and a great person. Despite being legally blind he would ride his bike a couple miles to catch a bus to work, day in and day out. He was killed when the driver of an automobile lost control on a very gentle curve, hit a guard rail, and then hit him:
https://democratherald.com/news/loca...688592d5e.html
Following an investigation it was determined that it was not likely that the State could prove criminal negligence beyond a reasonable doubt:
https://www.gazettetimes.com/news/lo...2af713158.html
So not every crash is caused by the narrow range of intoxicants and cell phones... I once responded to a crash where a person not familiar with our area drove straight off the road because they were looking at a waterfall that came over the ridge about a thousand feet above the valley floor. No drugs, no cell phone, just not paying attention.
I have driven the road where Grant was killed many times and had wondered how anyone who was not well past three sheets to the wind could lose control on that curve. Now I know. And that is why law enforcement departments have accident investigation teams.
I have had a vehicle steering system fail because a previous owner put SAE grade 2 bolts in a place where the manufacturer's shop manual specified that grade 5 or higher were required. Fortunately my event happened with nobody else on the road and I was able to maintain control well enough to come to a safe stop.