My girlfriend was driving her BMW convertible in Ascot and was waiting stationary at a T junction behind a Land Rover Discovery. The car in front of the Land Rover went to pull out then hesitated half way before then trying to reverse back. In turn the Land Rover reversed back hitting the front of our BMW despite my girlfriend sounding the horn. The lady got out of her car and admitted liability at the scene stating she was driving her husband's car as she had a broken her ankle whilst also wearing a cast/boot and had not seen her given the BMW’s low ride height. They exchanged details and but she has now changed her story to say my girlfriend drove into her. The insurance company has been out to see our BMW and estimate repairs of over £1,500. My girlfriend was stationary when the accident happened. I question should this lady have been driving with a cast on her foot and was she fit to be driving a motor car. As there are no witnesses to verify events so how can my girlfriend demonstrate she was not instrumental in causing the accident, are there specialist independent assessors who can prove this was not her fault by means of checking the engine management systems of the vehicles involved? More importantly now the BMW will be recorded as damaged it will affect the re-sale value how can one claim compensation and still protect her insurance NCB? We would very much appreciate your thoughts on the matter.