I think it is standard procedure to sue every time a trucking company is involved in an accident regardless of who is at fault. If the company is not in violation of a law it is more difficult to prove liability. I was involved in an accident when a vehicle driver went to sleep. There was no violation by me or the company. If a lawyer can find any violation even it it did not contribute to the accident he can persuade the jury to rule against the company. Something as simple as a light out can go against the trucking company.