I have been employed in the automotive collision repair industry for 10 years and have assesed not only the circumstances of collisions, but also the relative energy involved in wrecks based on the evident damage to the vehicles involved. This allows me to be able to determine, based on the damage areas of vehicles and the stresses involved, whether a specific party is being truthful in their account of the circumstances surrounding a car wreck. They are not "accidents", they are collisions, and there is always fault.