To: Stephanie Kollmann
From: Ed Mulvey
RE: Analyses of age groups
Date: December 5, 2012
When we met recently in Chicago, you asked whether we saw any marked differences according to age in our sample of serious adolescent offenders in the Pathways to Desistance study. This issue is obviously relevant for your work with the Illinois legislature regarding possible changes in the current state statute delineating the age of jurisdiction for the juvenile court. The Pathways sample is appropriate for looking for differences according to age groups because the sample consists of felony offenders from two major metropolitan locales. It is my understanding that part of the issue regarding the jurisdictional boundary of the court rests on whether 17 year old felony offenders are qualitatively different from felony offenders of age 14 and 15.
In your email to me, you posed three questions. I will give the short answer to each question, and then show you some results from our data that we relied upon to construct these answers.
- Do felony-charged 17-year-olds tend to become career criminals, or do they tend to cease criminal activity as they mature?
- In general, the serious offenders in our sample decrease offending over time (as measured in both self-reported antisocial activities and arrests). Because we know when these adolescents went in and out of institutions, we are able to calculate the number of arrests generated for the time they spent in the community (the rate of re-arrest rather than just the number of re-arrests). We looked at the rate of re-arrest for the different age groups over the seven year follow up period. This rate was not statistically significant among the groups, i.e., none of the three groups differed significantly from the others in their rate of re-arrest. In addition, none of the age groups differed from each other in the amount of time they spent in the community during the follow-up period. They were in institutional care (either juvenile facilities, jails, or prisons) for equivalent proportions of time.
- Do they desist in meaningfully different ways (rates, patterns) than felony-charged 16-year-olds?
- We identified five groups of adolescents who followed different patterns of offending over time. The different group patterns are shown in Figure 1. Two of these groups are of particular interest, i.e., those who persist in offending at high levels and those who drop off in their rate of offending over time. Each of these groups has roughly equivalent representation of 14, 16, and 17 year olds. Each of the identified groups with different offending patterns contains a mix of these age groups.
- In addition, if you then look at each of the age groups, you also see that the offenders in each age group distribute across the different offending pattern groups. Figure 2 shows what percent of each age group are found in the different offending trajectory groups. There is no significant association between age groups and the offending trajectory groups.
- Based on the results from Figures 1 and 2, the answer so far to the first two questions seems to be "no".
- Are felony-charged 17-year-olds LESS likely to reoffend as adults than felony-charged 14-year-olds?
- We did not run analyses to see the likelihood of having an adult arrest for each group because this would have required sorting through our arrest data to separate out juvenile and adult re-arrests for each study participant. It would have simply required too much work to re-arrange the data. Based on the above results, however, it seems unlikely that we would have found any group differences. If the groups are all showing the same rate of re-arrest and they are all spending about the same amount of time in the community, it seems logical to conclude that they are being arrested about the same number of times. There may be different likelihoods for getting arrested for particular types of crimes, but these analyses would be too involved to do right now. We do know that the sample as a whole decreases over the seven year period in the seriousness of the offenses that produce an arrest.
We conducted some other analyses to see if the different age groups looked different on background characteristics related to continued offending. We have developed seven composite measures indicating the level of risk/need that the adolescent has at the time of enrollment into the study. In these analyses, we saw that the 17-year old adolescents were at higher risk than the other two age groups concerning their antisocial peers, school performance, and substance use. The 14-year olds were at higher risk for their antisocial attitudes. There were no differences among the age groups on their levels of parental criminality, mental health problems, or criminal history. These differences are summarized on the next slide of the attachment to this email. The differences among the groups on the scales are shown in the figures that follow.
In terms of their risk for future offending, the 17 year olds seem to present a mixed picture. They are higher on some risk/need indicators and no different on others. They have accumulated several factors that increase their likelihood of continued offending, but are also addressable with targeted interventions (peers, school, and substance use). At the same time, they are not different in some of the more "set" factors related to future offending (parental criminality, mental health issues, and criminal history).
We hope that this information is useful. Please let us know if we can supply anything else.
Raising the Age of Juvenile Court Jurisdiction
The future of 17-year-olds in Illinois' justice system.
Illinois Juvenile Justice Commission