Forensic pathology is pathology that focuses on determining the explanation for death by examining a corpse. A post mortem is performed by a doctor , usually during the investigation of legal code cases and civil law cases in some jurisdictions. forensic pathologist is to work out how and why someone died, by doing an autopsy. it's important because we are the folks that actually get to state explanation for death on the death certificate, and that we even have the facility to testify our findings during a court of law.