How reliable is the bureau of motor carrier safety truck accident data?

This paper examines the degree of compliance with the accident reporting requirements imposed by the Bureau of Motor Carrier Safety (BMCS) of the U.S. Department of Transportation on motor carriers involved in interstate and foreign transport. It also examines the reliability and validity of the accident information reported by these carriers to the BMCS. The study shows that there is a high degree of accident underreporting, especially by the private and exempt carriers, and that the information reported on variables such as cargo weight, gross vehicle weights, and usage of seat belts at the time of accident, is biased toward the interests of the reporters of the accidents.