Criminal Law - Elements, Justification, Excuse and Participation
Criminal law questions test the structure of the offence. The examiner expects you to run the analysis in order: legality, act, mens rea, wrongfulness, culpability, then penalty.
Core rules
- No crime or penalty without a prior statutory text; analogy against the accused is prohibited.
- Material element: conduct, result, and causation. Moral element: intent (direct or indirect) or negligence where the law punishes it.
- Attempt requires commencement of execution and an intent to commit; voluntary abandonment may exempt from penalty.
- Participation: principal (perpetrator or co-perpetrator), inciter, and accomplice; the accomplice's liability is derivative and limited to the intended offence.
- Justification negates wrongfulness: lawful self-defence (current unlawful attack, necessity, proportionality), necessity, arrest of an offender, consent where the interest is disposable.
- Excuse negates culpability: minority, insanity, irresistible duress, and mistake of fact.
- Penalties: principal and accessory, mitigating and aggravating circumstances, concurrence of offences.
Worked example
A shopkeeper sees a thief running away with goods and stabs him in the back. The attack has ended, so self-defence is unavailable. Defence of property permits proportionate force to recover the goods, not lethal force against a fleeing person. If the shopkeeper acted in fear and exceeded proportionate defence, the court may apply excessive-defence rules, reducing the penalty; it does not acquit. If he had struck the thief during the struggle, proportionate self-defence would justify the act entirely.
Traps
Confusing justification (no unlawful act) with excuse (unlawful but not blameworthy); ignoring the timing of the attack; treating mistake of fact as mistake of law; forgetting that negligence liability requires an express text.