Background: As the first point of contact with the criminal justice system, police contact may provide an opportunity to identify those at risk of adverse mental health and other outcomes. At a population level, information on the contact young people have with police is lacking.

Objectives: This study aimed to establish the prevalence of first police contact for young people (as persons of interest, victims and witnesses), the patterns and sociodemographic correlates of contact and the incidence of first police contact for those identified with emotional and/or behavioural vulnerabilities at school entry.

Methods: In a NSW-based longitudinal, population-based sample of 79,802 young people followed to a maximum age of 14 years, record linkage methodology was employed to address the stated objectives, utilizing Cox proportional regression.

Findings: A total of 14.5% of children had had a first contact with police following school entry, with contact as a victim being most common. An increased incidence of police contact was identified for children assessed as having emotional and/or behavioural vulnerability at school entry, even after adjustment for key potential confounders.

Conclusions: Contact with police during childhood is not uncommon. Children with emerging emotional and behavioural vulnerabilities in early life may be at increased risk of early police contact. Identifying young people who make early contact with police may present an opportunity to intervene with a group of young people at risk not only of further contact with the criminal justice system, but a range of adverse outcomes including the development of mental illnesses.