Medical examiners and coroners commonly determine cause and manner of death without an autopsy examination. Some death certificates generated in this way may not state the correct cause and manner of death. From the case files of the Department of Forensic Medicine in Sydney, Australia, the authors retrospectively reviewed investigative information of all cases in a 6-month period that were initially considered natural deaths (429). The authors, blinded to autopsy results, accepted 261 cases as appropriate for certification without autopsy and assigned a cause of death to each. Per standard local practice, all cases had been autopsied. The actual causes of death as determined by autopsy were then revealed and compared with the presumed causes of death. Most presumed and actual causes of death were cardiovascular (94% and 80%, respectively). The majority of presumed causes of death were listed as ASCVD as the cases lacked features of a more specific cardiovascular process. A large majority of cases had a presumed cause of death of ischemic heart disease based on individual case details. The actual causes of death demonstrated a large breadth of cardiovascular and noncardiovascular disease processes, even though ischemic heart disease accounted for 62% of deaths. The presumed cause of death was completely wrong in 28% of cases. A nonnatural manner of death was present in 3% of cases. This study demonstrates that experienced forensic pathologists may generate erroneous death certificates for cases that are not autopsied.