Is the driver in the next lane awake?

I am hearing more and more about professional drivers getting into crashes after falling asleep.

Here's the latest:

SYLVAN TOWNSHIP, Mich. (AP) - Police say the drivers of two semi trucks apparently fell  asleep at the wheel about a mile apart in Washtenaw County, leading to separate crashes that snarled Interstate 94 traffic.
      Michigan State Police say the first crash happened about 3 a.m. Thursday on eastbound I-94 in Sylvan Township and the second happened about an hour later on westbound I-94 about a mile west of the first crash.
      Sgt. Chris Pascoe says neither driver was injured and no other vehicles were involved. He says the crashes about 45 miles west of Detroit appear to be a coincidence.
      Traffic was backed up near the site of the first Delays were minimal at the second crash site.
      Police say more delays were possible as cleanup continued.