Violent behaviour is part of being a normal teenage boy, a study has found, writes Natasha Gilbert.
David Smith and his colleagues at the School of Law, Edinburgh University, studied 4,300 young people who started secondary school in Edinburgh in August 1998.
They reported that the social class and household income of individual families had only a slight effect on the level of violent offending in boys.
Lesley McAra, one of the study's authors, said: "The study shows that violent boys are similar as people to those boys who are not (violent), suggesting that the phenomenon is a normal expression of masculinity for teenage boys."
In contrast, the researchers found significant differences between violent girls, non-violent girls and aggressive boys.
Dr McAra said that violent girls were much more likely to be drug users, gang members and from lower-class backgrounds.
Professor Smith said: "These findings suggest there is something about males, or a risk factor to which males are prone, that is implicated in serious offending."
The research, funded by the Economic and Social Research Council, also reports that young offenders are often the victims of crime themselves.
The study states that being a victim of crime at the age of 12 is one of the most powerful indicators that a child will offend at 15 and that offending at age 12 brings a strong possibility of victimisation at 15.
The researchers suggest that this link may be the result of a tendency in young offenders to group together and commit offences on each other, and that personality traits, such as impulsiveness and risk-taking, lead to offending and victimisation.
They propose that remedial programmes for young offenders and support services for the victims of crime should be reconsidered to take into account the fact that they will often be dealing with the same people.