A truck passes over the train tracks near a sign listing an emergency number for railroad problems on Tuesday, March 10, 2015, in Halifax, N.C.  A train collided with a truck, Monday injuring 55 people.  The truck with a state trooper escort become stuck in the crossing but no calls were made to Amtrak about the problem, even though the sign should have been visible to the truck driver.  (AP Photo /Jonathan Drew)

Truck driver in N.C. Amtrak crash has history of violations

Federal regulations require motor carriers to conduct background investigations before hiring truckers, but the companies have wide discretion when deciding whether to hire someone with poor driving records or criminal convictions.