Car damage caused by a pothole or by debris in the road might not be noticed immediately after it happens and it may be difficult to retrace a car’s route to show what specifically in the road caused the damage. Without other witnesses or other evidence , such as a police report or photos of the accident, the plaintiff’s testimony will be the only proof of how the damage was caused. If that is so, the agency may be able to argue that the plaintiff’s poor driving or other condition, such as the weather, was the real reason the damage occurred.
A 1985 US study showed that about 34% of serious crashes had contributing factors related to the roadway or its environment. Most of these crashes also involved a human factor.  The road or environmental factor was either noted as making a significant contribution to the circumstances of the crash, or did not allow room to recover. In these circumstances it is frequently the driver who is blamed rather than the road; those reporting the collisions have a tendency to overlook the human factors involved, such as the subtleties of design and maintenance that a driver could fail to observe or inadequately compensate for.