Thirty-seven pieces of plastic from Karen Read's taillight were found in the snow where Boston Police Officer John O'Keefe died. The prosecution says she backed over him with her SUV. The defense says those fragments were planted. Cadaver dogs alerted inside the house where she wasn't that night — and no one has fully explained it. This episode breaks down the forensic battle at the heart of the most divisive true crime case in America: the taillight glass analysis, the dog alerts, the bite marks, the digital timeline disputes, and what the retrial revealed. Two irreconcilable versions of what happened in Canton, Massachusetts on January 29, 2022. The Murder Tape Khronicles — new episodes every week.