The effectiveness of motor carrier safety audits

In 1986 the federal government expanded its program of company inspections for enforcement of motor carrier safety regulations. We find that many parts of these inspections are unrelated to the safety performance of firms. Never the less, reinspection of firms found to be unsatisfactory in a previous inspection does appear to bring about a substantial improvement in their safety performance. However, such firms represent a small fraction of the industry, and the probability of being inspected is very low. Thus, the program does not appear to have resulted in a detectable improvement in the accident rate of the industry.