Using statistical methods, researchers can figure out which factors in those kids' lives seem to steer them toward deviance. Clear patterns are emerging. Violent careers develop along two main paths. Early starters are more likely to become chronic, violent offenders. More commonly, children who turn to violence do so first in adolescence.
Some risk factors have more clout than others.
And their importance waxes and wanes through a child's life. For instance, a young child's life is centered in the home, and thus it's not surprising that a poor quality home life in the early years is particularly damaging. But hanging with antisocial peers is only a weak risk factor until kids hit adolescence and are straining to join the wider world. Then it becomes a huge influence. As factors pile up, so does risk.