The family of former Kansas City Chiefs star Derrick Thomas is not entitled to any money from General Motors for the January 2000 crash that killed the nine-time Pro Bowl linebacker, a jury reportedly ruled on Tuesday.

According to the Associated Press (AP), Thomas' mother, Edith Morgan, his seven children and their five mothers sued GM, seeking at least $US75 million - they claimed Thomas was fatally injured when the roof of his Chevrolet Suburban caved in during the crash.

The automaker's lawyers reportedly said during the trial that Thomas was killed not because of faulty design of his 1999 Suburban, but because he was driving too fast for the snowy conditions, and was ejected from the vehicle because he was not wearing his seat belt.

Thomas was paralysed from the neck down and died 16 days later, AP said. His best friend, Michael Tellis, who also was not wearing a seat belt, died at the scene. A third person in the vehicle - who was wearing a seat belt - walked away unharmed.

Michael Piuze, lawyer for Thomas' relatives, reportedly said he wasn't surprised by the decision.

"The problem with this case is that in the last four years since he got hurt, there has been an awful lot of publicity that Derrick Thomas was at fault, that Derrick Thomas was not wearing a seat belt," Piuze told AP.

General Motors lawyer John Hickey reportedly said the ruling sent a message that drivers should wear seat belts and drive safely.

"All we wanted to do is defend our car," Hickey told the Associated Press. "I feel bad for the Thomases. Mr. Thomas, unfortunately, was driving too fast."