My mom was a tribunal referee, had a case involving a traffic accident that had happened some three years earlier. The traffic policeman who came to give evidence had perfect recall of every little thing about the incident. Mom asked him how he was able to remember it all so clearly…
He said that firstly, while he attended lots of RTA, he had only actually seen two happen, this being one of them. Secondly, when he went to see the driver of the one of the cars (the one eventually found to be at fault), he at first thought she was having some kind of strange fit, her body was contorting itself in all manner of unusual ways. It turned out she had a ferret inside her shirt.