The driver was underneath the impact: Evidence ought to clearly show the driving force was impaired, ordinarily via a blood alcohol focus (BAC) of 0.08% or higher or proof of drug impairment. Criminal guidelines vary from state to point out, as do felony punishments, but felonies have a significant penalty: https://dui-lawyers.usattorneys.com/drunk-driving-causes-fatal-injury-to-motorcyclist-despite-legal-woes-for-san-diego-drivers/