none of the passengers in the back of the 10 - seat limo or the driver was wearing a seat belt .
the national transportation safety board is meeting ... ( associated press ) national transportation safety board ( ntsb ) chairman christopher hart speaks during an ntsb meeting at their headquarters in washington , tuesday , aug. 11 , 2015 , to determine the cause of an accident last ... ( associated press ) an accident description is displayed on a large screen as the national transportation safety board ( ntsb ) meets at their headquarters in washington , tuesday , aug. 11 , 2015 , to determine the cause of ... ( associated press ) but the board said the failure of morgan and other passengers in a limousine - van to wear seat belts and adjust headrests contributed to the severity of injuries when the limo was struck from behind by the truck .
roper 's attorney told abc news he would dispute the ntsb 's conclusions .
the driver of a wal - mart tractor - trailer that slammed into a limo carrying comedian tracy morgan and killed another comedian , the national transportation safety board said today .
though wal - mart provided fatigue information during its driver training , it was not required to have a fatigue management program , the ntsb said .
file - in this april 9 , 2014 , file photo , actor tracy morgan attends the fx networks upfront premiere screening of " fargo " at the sva theater in new york .
before starting his wal - mart shift , roper had driven 12 hours in his personal vehicle from his home in georgia to his base in delaware , according to the ntsb .
“ had the truck driver been traveling at the posted work zone speed limit of 45 mph , it could have been stopped before impact , ” ntsb investigator david rayburn said today .
add interest around 1 a.m. on june 7 , 2014 , 35 - year - old kevin roper – then halfway through the 13th hour of his 14 - hour shift – slammed into morgan ’s limo from behind , killing comedian james mcnair and seriously injuring morgan and three others .