Verified answer

First off, single car accidents. Second, is there any reason for the car to crash? Was there ice on the road? Did a tire blow? If there was no reason for the car to crash then what caused the crash. Lastly, most new cars have a computer that tracks steering, brake and gas inputs. If they run the computer and find the car was aimed at the cliff and gas was being applied so the car would speed up and no brake was used, then it is pretty sure the driver deliberately went over the cliff. (Keep in mind they can do this for anything so do not lie about what you were doing when the accident happened._

When the road is clean and bare, the car was in good condition, no one else was involved on the road.

Force of impact, isolated vehicle and secondary evidence such as history of suicidal ideation blah blah blah.....