The driver of the Walmart truck should not have been operating the vehicle, knowing that he had had no sleep for 24 hours. He should have taken a break, knowing that being tired while driving can cause an accident. In this case, he did cause a serious accident which caused several serious injuries and took a life. There is no excuse for this so charge him with murder.
The Wal-Mart driver that hit Tracy Morgan's vehicle should be charged with murder if the reports of inadequate sleep are correct. Professional truck drivers are required to have periods of rest and to document their driving and sleeping hours. If the driver did not sleep the required hours, he was being irresponsible and should be held accountable for his actions. Additionally, Wal-Mart should be fined for not overseeing their driver's hours.
The driver of the truck that crashed into Tracy Morgan's vehicle should not be charged with murder because it was not premeditated. He should be charged with manslaughter and criminal negligence for falling asleep at the wheel and killing someone. Technically, this is not murder, although it is still a very serious crime.
Of course there is a big law about criminal offenders, misdemeanors, felonies and so on... I think this case they have to evaluate the situation whether they guys is responsible for this crime or not. I think they can make a comment after investigating the situation and ending up with the right answer.