A lot of assumptions there. I don't know any people who are involved with it, I don't know any details about the accident (other than someone was killed and 3 people are facing manslaughter charges).
Your assumptions are highlighting my point... (unless you know more than what can be read in the paper)
If someone stepped in front of my car while I was driving in the city and died I would hope that everyone didn't assume that I was speeding and therefore should go to jail. Likewise I wont assume the 3 on charges could have avoided the situation... It may have been them at fault tho.