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Patterns of Juvenile Delinquency and Co-Offending

NCJ Number
Date Published
20 pages
This study used longitudinal data from Philadelphia to focus on co-offending in relation to age at first arrest.
Study subjects consisted of a random sample of 400 offenders drawn from police tapes that listed 60,821 crimes committed in Philadelphia during 1987. Because the researchers wanted to compare solo offending with co-offending, half the sample was drawn from a list of offenses the police had recorded as being solo offenses; the other half, was drawn from a list of co-offenses. Early starters were offenders whose first offense occurred before they were 13 years old (n=106). Late starters were offenders whose first offense occurred after achieving the age of 16 (n=103). The modal offenders (32.5 percent of the sample) were Black males whose first offense occurred when they were between 13 and 15 years old. Complete juvenile histories were tracked. The 400 identified offenders were listed for 1,843 crime incidents, for a mean of 4.61 incidents per offender. The analyses of offending in this randomly selected cohort of offenders active in an urban center during 1987 suggests that co-offending is a key ingredient in high rates of criminality. Co-offending should become a feature in analyzing crime rates and understanding changes in them. Co-offending is also central to understanding individual differences in recidivism. Co-offenders should become targets of interventions strategies. An understanding of the mechanisms by which peers influence intentional behavior should become a focus for theoretical developments. Not only are those who first offended before age 13 most likely to be co-offenders, but the size of their offending groups are most likely to be large. A young co-offender is likely to seek out co-offenders and to commit additional crimes. Ignoring co-offending in the computation of crime rates may result in significantly misleading reports regarding public safety and the effects of incarceration. It further suggests that the mechanisms of peer influence on intentional action deserve attention and that a theory of criminal behavior ought to provide an account of these influences. 1 table and 35 references

Date Published: January 1, 2001