Family type and criminal behaviour of male offspring: the Northern Finland 1966 Birth Cohort Study.

Background: Unstable family environment during childhood is known to predispose to juvenile delinquency.

Aims: This study explored whether childhood family structure is associated with violent behaviour of adult offspring.

Methods: We used a large, unselected general population birth cohort (n = 5589 males) linked with the national crime registers (up to the age of 32 years). The Ministry of Justice provided information on registered offences for all subjects. A logistic regression analysis was performed to examine the association between family type and criminality (violent and non-violent crimes).

Results: We found that single-parent family "at birth" (adj. OR 3.6, 95% CI 1.8-7.0) and "all time" (up to the age of 14 years) (adj. OR 5.2, 95% CI 2.5-10.6) were risk factors for violent offences of an adult offspring. Also parental death (adj. OR 2.2, 95% CI 1.3-3.6) and divorce (adj. OR 2.5, 95% CI 1.6-3.7) doubled the risk for violence. Non-violent offences were associated only with parental death and, divorce.

Conclusions: A single-parent family of origin is strongly associated with later violent criminality of male offspring. Further studies are needed to explore the psychosocial aspects of single-parent family environment which may promote the vulnerability to violent offending in adulthood.