Mitigating factors are usually around mental health and caring / supporting family.Which mitigating factors might they be, he was drunk to his eyeballs, swimming in the stuff, got in the car, with a 'mate' , then proceeded to smash the town up ! Were there any aggravating circumstances , er let me see ,NO !
Remember the point is to both punish and rehabilitate.
Agreed that the passenger has some culpability here.