How does life course theory help us understand the fact that nearly all serious adult offenders were serious juvenile offenders even as most serious juvenile offenders do not become serious adult offenders?

Life course theory suggests that there is a correlation between the choices a person is currently making in his or her life and the historical path the person has traveled thus far. In more simplistic language, life course theory says that our past decisions drive our future actions. Therefore, adult offenders with a history of serious juvenile offenses are staying on their given path and are making decisions based on their past choices.
Given the young age of juvenile offenders, they are usually just beginning to make choices related to criminal actions. They do not have years of criminal behavior driving their decision-making. They have the chance to select another life path, which many do. However, if they continue down the path of criminal action, they are creating a social context in which they are a criminal. The more criminal acts they commit, the more solidified their life path becomes.
Life course theory also suggests that major life events can create trajectories in an individual’s life path. As young adults move into adulthood (a major life event), they may veer off their current path. Therefore, if an adolescent is participating in criminal acts, the move into adulthood may result in different decisions regarding criminal activity.
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