Since the 1990's, implementation of zero tolerance policies in schools has led to increased use of school suspension and expulsion as disciplinary techniques for students with varying degrees of infractions. An unintended consequence of zero tolerance policies is that school suspension or expulsion may increase risk for contact with the juvenile justice system. In the present study, we test how forced absence from school via suspension or expulsion and chosen absence from school (truancy) are associated with the likelihood of being arrested. Using month-level data from 6,636 months from a longitudinal study of delinquent adolescents (N = 1,354; 13.5 % female; 41.5 % Black, 33.5 % Hispanic-American, 20.2 % White), we compare the likelihood of being arrested, within individuals, for months when youth were and were not suspended or expelled from school and for months when youth were and were not truant. Finally, we test if these associations were moderated by stable demographic characteristics (sex, race, age, history of problem behaviors) and time-varying contextual factors (peer delinquency, parental monitoring, and commitment to school). Being suspended or expelled from school increased the likelihood of arrest in that same month and this effect was stronger among youth who did not have a history of behavior problems and when youth associated with less delinquent peers. Truancy independently contributed to the likelihood of arrest, but this association was explained by differences in parental monitoring and school commitment. Thus, school disciplinary action places youth at risk for involvement in the juvenile justice system and this may be especially true for less risky youth.

Some evidence suggests that youth who use marijuana heavily during adolescence may be particularly prone to health problems in later adulthood (e.g., respiratory illnesses, psychotic symptoms). However, relatively few longitudinal studies have prospectively examined the long-term physical and mental health consequences associated with chronic adolescent marijuana use. The present study used data from a longitudinal sample of Black and White young men to determine whether different developmental patterns of marijuana use, assessed annually from early adolescence to the mid-20s, were associated with adverse physical (e.g., asthma, high blood pressure) and mental (e.g., psychosis, anxiety disorders) health outcomes in the mid-30s. Analyses also examined whether chronic marijuana use was more strongly associated with later health problems in Black men relative to White men. Findings from latent class growth curve analysis identified four distinct subgroups of marijuana users: early-onset chronic users, late increasing users, adolescence-limited users, and low/nonusers. Results indicated that the four marijuana use trajectory groups were not significantly different in terms of their physical and mental health problems assessed in the mid-30s. The associations between marijuana group membership and later health problems did not vary significantly by race. Findings are discussed within the context of a larger body of work investigating the potential long-term health consequences of early-onset chronic marijuana use, as well as the complications inherent in studying the possible link between marijuana use and health effects.

Objective Adolescents who regularly use marijuana may be at heightened risk of developing subclinical and clinical psychotic symptoms. However, this association could be explained by reverse causation or other factors. To address these limitations, we examined whether adolescents who engage in regular marijuana use exhibit a systematic increase in subclinical psychotic symptoms that persists during periods of sustained abstinence. Method The sample comprised 1,009 boys who were recruited in 1st and 7th grades. Self-reported frequency of marijuana use, subclinical psychotic symptoms, and several time-varying confounds (e.g., other substance use, internalizing/externalizing problems) were collected annually from age 13 to 18. Fixed effects (within-individual change) models examined whether adolescents exhibited an increase in their subclinical psychotic symptoms as a function of their recent and/or cumulative history of regular marijuana use, and whether these effects were sustained following abstinence. Models controlled for all time-stable factors (default) and several time-varying covariates as potential confounds. Results For each year adolescents engaged in regular marijuana use, their expected level of subsequent subclinical psychotic symptoms rose by 21% (p <.05) and their expected odds of experiencing subsequent paranoia or hallucinations rose by 133% (p < .001) and 92% (p < .05), respectively. The effect of prior regular marijuana use on subsequent subclinical psychotic symptoms persisted even when adolescents stopped using marijuana for a year. Findings remained significant after controlling for all time-stable and several time-varying confounds, as well as possible reverse causation. Conclusions These results suggest that regular marijuana use may significantly increase the risk that an adolescent will experience persistent subclinical psychotic symptoms.

There is some suggestion that heavy marijuana use during early adolescence (prior to age 17) may cause significant impairments in attention and academic functioning that remain following sustained periods of abstinence. However, no longitudinal studies have examined whether both male and female adolescents who engage in low (less than once a month) to moderate (at least once a monthly) marijuana use experience increased problems with attention and academic performance, and whether these problems remain following sustained abstinence. The current study used within-individual change models to control for all potential pre-existing and time-stable confounds when examining this potential causal association in two gender-specific longitudinal samples assessed annually from ages 11 to 16 (Pittsburgh Youth Study N=479; Pittsburgh Girls Study N=2296). Analyses also controlled for the potential influence of several pertinent time-varying factors (e.g., other substance use, peer delinquency). Prior to controlling for time-varying confounds, analyses indicated that adolescents tended to experience an increase in parent-reported attention and academic problems, relative to their pre-onset levels, during years when they used marijuana. After controlling for several time-varying confounds, only the association between marijuana use and attention problems in the sample of girls remained statistically significant. There was no evidence indicating that adolescents who used marijuana experienced lingering attention and academic problems, relative to their pre-onset levels, after abstaining from use for at least a year. These results suggest that adolescents who engage in low to moderate marijuana use experience an increase in observable attention and academic problems, but these problems appear to be minimal and are eliminated following sustained abstinence.

Although impulsivity is one of the strongest psychological predictors of crime, it is unclear how well impulsivity, measured at a specific moment in adolescence, predicts criminal behavior months or years into the future. The present study investigated how far into the future self-reports and parents' reports of a youth's impulsivity predicted whether he engaged in illegal behavior, whether one reporter's assessment was more predictive than the other's, and whether there is value in obtaining multiple reports. Data were obtained from a 6-year longitudinal study of adjudicated juvenile offenders (n = 701 mother-son dyads). Youth (m = 15.93 years old; sd = 1.14) and their mothers independently reported on adolescents' impulsivity at the initial assessment. We examined the prospective correlation of these measures with illegal behavior, assessed by official records of arrests and youths' self-reports of offending across the 72-month study period. Youths' and mothers' reports of the adolescents' impulsivity were weakly, but significantly, correlated with one another. Furthermore, mothers' ratings of their sons' impulsivity predicted arrest up to 6 years into the future, whereas youths' reports did not significantly predict arrest beyond 30 months. With respect to youths' self-reports of offending, mothers' ratings of impulsivity again predicted farther into the future (as late as 6 years later) than did youths' self-reports of impulsivity, which were not predictive beyond 4 years. However, across the first 4 years, youths' self-reports of impulsivity explained more variance in self-reported offending than did mothers' ratings. The results underscore the endurance of the predictive utility of an assessment of impulsivity and the importance (and accuracy) of parents' reports of developmental constructs, even when their children are adolescents.