Crime and the Criminal Justice System
Core concepts
Understand the elements of a crime: actus reus (the prohibited conduct) and mens rea (the guilty mind), plus the absence of a defence. Know the burden and standard of proof - the prosecution proves the case beyond reasonable doubt; the accused bears an evidential burden for some defences. Learn categories of offence (summary versus indictable), the role of police, prosecution and defence, bail, and sentencing purposes (punishment, deterrence, rehabilitation, protection, denunciation).
Understand defences: self-defence, duress, necessity, insanity, automatism, and intoxication (generally not a complete defence except where it negates mens rea). Know strict liability offences, where mens rea need not be proved. Understand the rights of the accused: presumption of innocence, right to silence, legal representation, and a fair trial.
Traps
Do not say the accused must prove innocence; the burden lies with the prosecution. Do not treat intoxication as always a defence. Avoid confusing summary offences (magistrates) with indictable offences (higher courts, often jury). Do not claim bail is a determination of guilt.
Worked example
A person charged with assault claims self-defence. The prosecution must disprove self-defence beyond reasonable doubt once raised. Rule of thumb: identify the offence elements, then the defence, then who bears the burden, then the standard.
Sentencing
Consider aggravating and mitigating factors, mandatory sentencing, and restorative justice approaches, and evaluate whether punishment achieves its stated purposes.