<P> They collect and interpret toxicological analyses on body tissues and fluids to determine the chemical cause of accidental overdoses or deliberate poisonings . </P> <P> Forensic pathologists work closely with the medico - legal authority for the area concerned with the investigation of sudden and unexpected deaths: the coroner (England and Wales), procurator fiscal (Scotland), or coroner or medical examiner (United States). </P> <P> They serve as expert witnesses in courts of law testifying in civil or criminal law cases . </P> <P> In an autopsy, the forensic pathologist is often assisted by an autopsy / mortuary technician (sometimes called a diener in the US). </P>

What does a pathologist do at a crime scene