Principle
The Gate of Legality
No crime and no punishment without a clear, pre-existing law.
Nullum crimen sine lege
A person may not be convicted of a crime unless the conduct was recognised as a crime BEFORE they engaged in it, and may not be punished more severely than the law allowed at that time. The State's power to punish is limited by law — this is the principle of legality, entrenched by the right to a fair trial (s 35(3) of the Constitution) and the rule of law (s 1).
The Five Rules
- IUS ACCEPTUM — only conduct that the law (statute or existing common law) already recognises as a crime is punishable; courts may not create new crimes
- IUS PRAEVIUM — the crime must have existed when the accused acted; no retrospective creation or extension of crimes (Masiya)
- IUS CERTUM — crimes must be defined clearly and precisely; a vague crime offends legality
- IUS STRICTUM — penal provisions are interpreted strictly and are not extended by analogy against the accused
- NULLA POENA SINE LEGE — no penalty without a pre-existing law; the punishment may not exceed that fixed when the offence was committed (Veldman)
Legality = nullum crimen, nulla poena sine praevia lege certa. Remember the five rules: ius acceptum, praevium, certum, strictum, and nulla poena.
Exam trap: courts CAN develop the common law, but they may not apply a newly-created or extended crime retrospectively to the accused before them (Masiya). Development operates only for the future.
Ius praevium
No Retrospective Crimes
The crime and its penalty must pre-date the conduct.
Non-retrospectivity
Neither the definition of a crime nor its punishment may be applied retrospectively to the accused's disadvantage. A court may develop or extend a common-law crime, but only prospectively — the accused before the court must be judged on the law as it stood when they acted.
Punishment too
Nulla poena sine praevia lege protects the penalty as well as the crime: an accused may not receive a heavier sentence than the maximum applicable when the offence was committed (s 35(3)(l) and (n) of the Constitution).
No retrospective crimes and no retrospective punishment. Judicial development of crimes binds only future conduct, never the accused in whose case it is announced.
Key Cases — Ius Praevium & Nulla Poena
S v Masiya2007 (2) SACR 435 (CC)Rape's common-law definition could be extended (to include anal penetration) but not applied retrospectively to Masiya — ius praevium bars retrospective extension of crimes.
Facts. The accused was convicted of raping a nine-year-old girl by anal penetration. At the time the common-law definition of rape covered only unlawful vaginal penetration of a woman; anal penetration would have been indecent assault. The lower courts sought to extend (develop) the common-law definition of rape to include anal penetration.
Legal question. May a court develop the common-law definition of a crime to the accused's disadvantage, and if so, may the extended definition be applied retrospectively to the accused before the court?
Judgment. The Constitutional Court extended the common-law definition of rape to include anal penetration of a female, but held that this extension could not be applied retrospectively to Masiya. Applying it to him would offend the legality principle and his fair-trial rights.
Significance. The leading modern authority on ius praevium and the limits of judicial development of crimes: the courts may develop crimes, but not so as to convict the accused before them on a definition that did not exist when they acted. (Rape has since been fully codified and made gender-neutral by the Sexual Offences Act 32 of 2007.)
Exam tip. Use Masiya for the legality principle — specifically ius praevium (non-retrospectivity) and the limits on developing crimes. Note the split: the definition was extended for the future, but not applied to Masiya himself.
Veldman v Director of Public Prosecutions2007 (3) SA 210 (CC)An increased sentencing jurisdiction may not be applied retrospectively — no heavier penalty than the law allowed when the offence was committed (nulla poena).
Facts. After the accused had been convicted, but before sentence, the penal jurisdiction of the court was increased. A heavier sentence was then imposed than was competent when the offence was committed and the trial began.
Legal question. May an increased sentencing jurisdiction be applied retrospectively, so that an accused receives a heavier penalty than the one applicable when the offence was committed?
Judgment. The Constitutional Court held that the retrospective application of the increased sentencing jurisdiction was unconstitutional; the accused could not be sentenced more heavily than the law allowed when he committed the offence.
Significance. The leading authority applying the legality principle (nulla poena) to punishment — the non-retrospectivity guarantee protects the accused not only as to the crime but also as to the penalty.
Exam tip. Use Veldman for the punishment limb of legality (nulla poena sine praevia lege). Pair with Masiya (ius praevium as to the definition of the crime).
Certum & Strictum
Clear and Strict
Crimes must be clearly defined and strictly construed.
Ius certum
A crime must be formulated clearly and precisely enough that people can know in advance what is prohibited. A crime (or statutory provision) so vague that its meaning cannot reasonably be ascertained may be struck down as unconstitutional (the void-for-vagueness doctrine).
Ius strictum
Penal provisions are interpreted strictly. A court may not extend a crime by analogy to cover conduct that falls outside its terms merely because that conduct seems equally blameworthy. Ambiguity is resolved in favour of the accused.
Ius certum = crimes clearly defined (no vague crimes). Ius strictum = strict interpretation, no reasoning by analogy to the accused's disadvantage.
Exam trap: do not "read in" conduct that the definition does not cover just because it is similar. That is analogy, which ius strictum forbids — the remedy is legislation, not conviction.