In Australia, the statutory minimum age of criminal responsibility is 0 years, with a presumption (known as doli incapax) deeming a child between the ages of 0 and 4 incapable of committing a criminal act. From 4 to 7 young offenders may be held fully responsible for their criminal acts but are subject to a different range of criminal sanctions than adults committing the same offences (Australian Institute of Criminology, 2005). This age range aligns with the biological processes of puberty which typically take place between 0-22 and can vary from culture to culture, usually occurring between 0-3 years (Early Adolescence) to about 8-22 years (Late Adolescence).
During this period of Adolescence an individual experiences dramatic changes in anatomy, physiology, and physical appearance as they biologically prepared for sexual reproduction. These changes all begin with events that occur in the endocrine system during puberty which trigger hormonal and physical changes as well as dramatic changes in identity, selfconsciousness and cognitive flexibility (Blakemore & Choudhury, 2006, p296). Importantly, these changes
in brain development and cognitive systems mature along different timelines throughout Adolescent creating a period of especially heightened vulnerability. The prefrontal cortex, which is responsible for performing of complicated tasks involving long-term planning, the regulation of emotion, impulse control, and the evaluation of risk and reward continues to develop well into late adolescence (Steinberg & Scott, 2003, p03). This coupled with changes in early adolescent to the limbic system around puberty may stimulate adolescents to seek higher levels of novelty and to take more risks without the capacity to assess or consider the impact of their decisions and/or assess the risks of their actions. As Smith, Chein & Steinberg notes; the cognitive mechanisms associated with deliberation follow a linear and protracted developmental trajectory that extends into adulthood, well beyond the most striking period in pubertal development, whereas the processes that underlie affective responding exhibit an inverted U-shaped pattern of developmental change that is most dramatic during the first part of adolescence (p 236).