Systematic autopsy was performed in 807 medicolegal deaths where the police had not requested autopsy. In all cases both the cause of death and the mode of death had been reported at the medicolegal external examination. The autopsy revealed differences in the mode of death in about 4% of all cases. This was due in particular to the problems associated with distinguishing presumed natural deaths from accidents and suicide. The cases of "concealed" suicide were found in particular among the higher age groups. However, no characteristic relationship was found between the proportion of differing modes of death and the age groups. All cases of homicide were recognized at the medicolegal external examination. Malignant disease that had not been diagnosed previously was found in about 4% of the cases, the reason being the large proportion of elderly subjects in the material. Syphilitic aortitis that had not been previously diagnosed was demonstrated in about 1% of all cases, and pulmonary tuberculosis that had not been previously diagnosed was demonstrated in 0.7% of the cases. The conclusion is that the results provide no support for replacing the medicolegal autopsy by medicolegal external examination alone, but rather suggest that the proportion of medicolegal autopsies should be increased.