the morning, pounding on doors, trying to get them to call someone to come help her. >> putting yourself at the scene? >> correct. >> reporter: and if the crux of the prosecution's case was the science, the defense was more than happy to make this a case of dueling science. >> you knew early on it was going to be a battle of science, expert versus expert? >> yes. >> reporter: and if weighty resumes counted, the defense expert maybe had the edge. he'd performed or supervised more than 62,000 autopsies. his name? dr. werner spitz. >> i'm not sure there's a better cv for a forensic pathologist that you could find. >> the brain. >> reporter: renowned for his work in historic cases like the jfk assassination and more recent sensational cases like casey anthony, dr. spitz had even written the textbook for pathologists, and he disagreed with everything the coroner had to say. >> dr. barnett's opinion was that these fractures that you see in this photo were caused by