Drivers are supposed to operate their vehicles at a safe rate of speed for the conditions. You'd think not slowing down in an area with a lot of kids and a bus would constitute negligent behavior, but it's completely legal in PA to kill people with your car as long as you weren't drinking or on drugs.

 
Last summer outside Pittsburgh, a driver creamed a guy in a crosswalk on Rt. 51 and killed him. Charges weren't even discussed.