Adolescent homicides in Finland: offence and offender characteristics.

Approximately 9% of the homicides in Finland are committed by adolescents under 20 years of age. The purpose of this study was to investigate the offence and offender characteristics in homicidal adolescents. Forensic psychiatric evaluation statements of adolescent offenders accused of a homicide during 1990-2001 were reviewed retrospectively (n=57). In 38% of the cases, there were multiple offenders. In 58% of the cases, the victim was an acquaintance, in 25% a stranger, in 12% a family member and in 5% of the cases an (ex)intimate partner. Sixty-nine percent of the offenders were intoxicated and 21% under the influence of drugs at the time of the killing. The most frequent motives were an argument (25%) and a robbery (25%). Sixty-four percent of the offenders had developmental problems and 42% had a crime history. Approximately half were diagnosed as having a conduct or a personality disorder, but 32% of the offenders were considered not to suffer from a mental illness or substance abuse. For 63%, the level of intellectual functioning was average or above average. There were signs of more than one form of violence in 54% of the cases and 28% of the cases contained excessive violence. The use of multiple and excessive violence was significantly related to the offender age, multiple offenders, offender-victim relationship and substance abuse, but not related to having developmental problems, crime history or mental illness.