I suppose with the G sensor in the smart phones now, maybe they can prove that some dick was texting at the moment of impact

It's a tough one, as any conversation or radio is distracting to some degree.
Two way radios in vehicles as well

New larger vehicles now have head up displays onto the windscreen for phones and movies

I tried out the new auto steer on a 300hp tractor taking it out to the farm and I didn't have to override the steering wheel, for the whole 32kms of the trip. (except to pull over to let traffic past.)
GPS accurate to 8.5mm. Proximity sensors to 100mtrs in all directions. The severity of audible "chirp" increases as vehicles approach.
This will be slaved to another tractor so only one operator for the two tractors.
Corner approaching, says and the digitized lovely lady counting down the distance it meters to the turn. At 10mtrs she pauses the DVD till the intercept with the new line is confirmed and locked and then the movie resumes.
This is only for agriculture and mining. (for the time being)