The age at which an individual first experiments with illicit drugs has been of significant interest to policymakers and practitioners, primarily because research has persistently shown a link between early juvenile onset of drug use and less favourable health and criminal justice outcomes in adulthood.
drug users who have regular contact with the criminal justice system typically commenced their drug use at earlier ages (Gaffney et al. 2010; Johnson 2001);
even within the drug-using offender population, those with a recent history of violent or prolific property offending typically commenced drug use and progressed to regular drug use earlier than those with no such history (Makkai & Payne 2003); and
the risk that an offender will progress to serious and frequent offending was highest when both drug use and offending first began at younger than average ages (Payne 2006).
Although there is broad agreement that early initiation into drug use and subsequent involvement in the criminal justice system are correlated, there still remains considerable debate regarding the direction of causality.
Some suggest that early drug use can act as a gateway or ‘stepping stone’ to more significant drug use and other problem behaviours (Kandel, Yamaguchi & Chen 1992), while others argue that drug use does not cause criminal behaviour, but rather, there is a shared or common aetiology, such as low self control or high impulsivity (Gottfredson & Hirschi 1990).