If he could not shift over quick enough he was moving too fast, or he was too impaired to shift in time.
8:30 PM,Northbound. doesn’t say what direction that stretch of road is. Evening sun could have been in his eyes. Buggy may not have had prominent tail lights. Slow moving buggy.
No excuse. Going too fast to avoid collision. Driver may or may not have been intoxicated. Shock of his hitting
buggy may have made him appear to the police officer to be
under influence of some drug. Lab test will tell. I have followed many Schneider trucks, many times and they were always traveling at a safe speed.