The authors report on three autopsy cases in which the findings at the death scene gave rise to the suspect of non-natural, in two cases even violent causes of death. The medico-legal and criminalistic investigations led to surprising results: Death was due to acute intoxication with narcotics, supposed delirium tremens and a suicide attempt in the presence of bronchopneumonia. External force was ruled out in all three fatalities by cooperative work of police investigators and forensic medicine.