By Ben Matthews, Susan McVie, Carleen Thompson & Anna Stewart.

This brief is based on the following paper: Matthews, B., McVie, S., Thompson, C., & Stewart, A. From Childhood System Contact to Adult Criminal Conviction: Investigating Intersectional Inequalities using Queensland Administrative Data. J Dev Life Course Criminology 8, 440–480 (2022).

1. What problem does your research address? Why is this significant?

People who experience youth justice contact are far more likely than others to receive criminal convictions in adulthood [1]. Children who have contact with both youth justice and child welfare services—so-called cross-over children—are at increased risk of penetrating most deeply into the justice system [2] and may be more likely to have persistent adult criminal careers [3]. In addition, the relationship between childhood experiences and adult criminal careers differs by both sex and race/ethnicity [4]. However, previous research doesn’t show whether cross-over effects apply equally to everyone or reflect intersectional inequalities for boys and girls from different racial/ethnic backgrounds.

Examining the complex relationship between early system contact and adult conviction outcomes by sex and race/ethnicity is difficult to do using standard statistical models. Our research uses a cutting-edge statistical model to explore the cumulative effects of child welfare and youth justice system contact on adult conviction trajectories, and whether these associations vary by sex and race/ethnicity. It is important because it could inform the development of policies that prevent negative outcomes for cross-over children and reduce inequalities amongst children from different backgrounds who get involved in formal systems of intervention.

2. How did you conduct your research?

We used administrative data from the Queensland Cross-sector Research Collaboration [5] (QCRC) on 83,371 people born in 1983 and 1984 and followed up to age 29. QCRC includes information linked across multiple government administrative systems, including information from health, child protection, criminal justice systems, and births, deaths and marriages. We define ‘cross-over children’ as any individual who had contact with both the youth justice and child welfare systems under the age of 17.

We used an exploratory methodological approach to examine the cumulative effects of having both child welfare and youth justice contact on adult conviction outcomes, and how this varied by sex and Indigenous status. First, we identified different trajectories (or pathways) of criminal conviction in adulthood. Then, we used a statistical model to quantify the overlapping relationships between sex, Indigenous status [6], child welfare contact and youth justice contact, and adult conviction trajectory.

3. What are your major findings?

People who had contact with justice or welfare systems in childhood were more likely to be convicted in adulthood than those who did not; however, cross-over children had the highest likelihood of conviction. This was true for both men and women and both Indigenous and non-Indigenous Australians. Around 77% of people who had contact with both child welfare and youth justice systems went on to have a criminal conviction by age 29. This compares to 52% of people who had contact with youth justice only, 28% of people who had contact with child welfare only, and 13% of people who had no contact with either youth justice or child welfare.

We identified five ‘conviction trajectories’ which varied in seriousness according to the trend and volume of convictions in adulthood (see Figure One): No/Low convictions, Low/Declining, High/Declining, Low/Increasing and High/Persistent. Contact with both justice and welfare systems in childhood was associated with increased severity of conviction trajectories in adulthood. Again, this was true for both men and women and both Indigenous and non-Indigenous Australians. Overall, likelihood of conviction was higher for men than women, and for Indigenous Australians compared to non-Indigenous Australians, with Indigenous men having the highest likelihood of conviction in adulthood. However, these overall differences in justice system involvement must be interpreted in the light of former and current systemic injustices experienced by Indigenous peoples in Australia.

Figure One: Estimated trajectories of adult criminal conviction in QCRC sample

We found a cumulative association between cross-over status in childhood and conviction outcome in adulthood, which means that cross-over children from all backgrounds were likely to have a more serious conviction trajectory than children with youth justice or child welfare contact only. The result of this cumulative association was greater equity of negative outcomes across all groups. In other words, both men and women from Indigenous and non-Indigenous backgrounds had much more similar, and serious, conviction trajectories if they were cross-over children. Nevertheless, Indigenous men continued to have the most serious conviction profile overall.

There was evidence of additional inequality from being a cross-over child (over-and-above the association between child welfare contact or youth justice contact in isolation) only for non-Indigenous women, who had the lowest likelihood of conviction and the least serious trajectory. 

4. What does your research mean for policy and practice? Our research demonstrates the value of examining adult conviction patterns amongst people from a range of backgrounds (in this case, cross-over status, sex and race) in order to identify underlying factors that may influence different outcomes. 

The finding that cross-over status in childhood increases the similarity of adult conviction outcomes in a negative way suggests that work needs to be done to reduce the likelihood of all cross-over children (not just those from certain backgrounds) going on to have criminal convictions. This is in line with other research that highlights the potential damaging effects of early system contact, and the importance of diversion from formal interventions [7].

The finding that cross-over status had an additional inequality effect amongst non-Indigenous girls might suggest that they are deserving of particular attention; however, given that their adult conviction outcomes were the least severe overall, additional attention to this group may be disproportionate.

Although cross-over status was associated with more similar conviction outcomes for all groups, it is important to recognise that Indigenous boys had the worst conviction outcomes overall (with or without childhood system contact). Importantly, we cannot interpret these differences as reflecting ‘deficits’ amongst Indigenous people in individual or familial factors associated with offending risk, because adult convictions are the result of complex factors which also include the effects of poverty, policing and the legacy of colonialism. Regardless it is clear that underlying intersectional inequalities in Australian society need to be addressed as a matter of urgency. 


We sincerely thank the representatives from the Queensland Government Statistician’s Office, Queensland Police Service, Queensland Department of Justice and Attorney-General, the Department of Children, Youth Justice and Multicultural Affairs and the Queensland Registry of Births, Deaths and Marriages for the considerable support they provided for this project. The views expressed are not necessarily those of the departments or agencies, and any errors of omission or commission are the responsibility of the authors. The authors gratefully acknowledge use of the services and facilities of the Griffith Criminology Institute’s Social Analytics Lab at Griffith University.


[1] McAra, L., & McVie, S. (2010). Youth crime and justice: Key messages from the Edinburgh Study of Youth Transitions and Crime. Criminology and Criminal Justice, 10(2), 179–209.; Craig, J. M., Stewart, A., & Hurren, E. (2020). Are Dual-System Offenders Different?: An Examination of Prevalence and Specialization in Criminal Offending and Child Maltreatment Perpetration. International Journal of Offender Therapy and Comparative Criminology.

[2] Bromwich, R. J. (2019). Cross-over youth and Youth Criminal Justice Act evidence law: Discourse analysis and reasons for law reform. Manitoba Law Journal, 4, 265–290; Herz, D. C., Ryan, J. P., & Bilchik, S. (2010). Challenges facing crossover youth: An examination of juvenile-justice decision making and recidivism. Family Court Review, 48(2), 305–321.; Kolivoski, K. M., Goodkind, S., & Shook, J. J. (2017). Social justice for crossover youth: The intersection of the child welfare and juvenile justice systems. Social Work, 62(4), 313–321.

[3] Baidawi, S. (2020). Crossover Children: Examining Initial Criminal Justice System Contact Among Child Protection-Involved Youth. Australian Social Work, 73(3), 280–295.; Baidawi, S., & Sheehan, R. (2019). ‘Cross-over kids’: Effective responses to children and young people in the youth justice and statutory Child Protection systems. Report to the Criminology Research Advisory Council. Australian Institute of Criminology.

[4] Broidy, L. M., Stewart, A. L., Thompson, C. M., Chrzanowski, A., Allard, T., & Dennison, S. M. (2015). Life Course Offending Pathways Across Gender and Race/Ethnicity. Journal of Developmental and Life-Course Criminology, 1(2), 118–149.

[5] Stewart, A., Dennison, S., Allard, T., Thompson, C., Broidy, L., & Chrzanowski, A. (2015). Administrative data linkage as a tool for developmental and life-course criminology: The Queensland Linkage Project. Australian & New Zealand Journal of Criminology, 48(3), 409–428.; Stewart, A., Ogilvie, J. M., Thompson, C., Dennison, S., Allard, T., Kisely, S., & Broidy, L. (2021). Lifetime prevalence of mental illness and incarceration: An analysis by gender and Indigenous status. Australian Journal of Social Issues56(2), 244-268 [1] McAra and McVie, ibid.

[6] In this article, we respectfully refer to Aboriginal and Torres Strait Islander Peoples as Indigenous Australians or Indigenous Peoples.

[7] McAra and McVie, n 1.