Estimated rates of disorders among perpetrators of homicide can vary considerably depending on the sample chosen (e.g., exclusion or inclusion of individuals ordered to psychiatric hospitals) and the sources of diagnostic information. Northern European studies have had the benefit of psychiatric data on a substantial portion of individuals convicted of homicide within a defined geo- graphic area regardless of ultimate judicial disposition. Additionally, the arrest and prosecution rates in Scandinavian countries are high, and information is available on a large proportion of offenders (4, 8).