911 what is your emergency? Yeah I'm behind this vehicle and they're driving way too slow and drifting all over the road. I think they've been drinking.  Better just to stick with the good old fashioned break check, but only if they look like they'll have insurance. A rear end accident is automatic fault for the person that hits you. Of course now days depending on where you live getting out of your car if you get rear ended is a good way to get jacked.