Mental illness
The House of Delusion
When does mental illness make an act void?
Definition & extension
A person is mentally ill when they cannot understand the nature and legal consequences of their acts. Lange v Lange extends this: a person is still mentally ill where they understand the act but are motivated by delusions caused by mental illness.
Presumption & onus
Everyone is presumed sane until the contrary is proved; the onus is on the party alleging incapacity. Open every answer with the presumption.
Effect
Contracts are VOID (but enrichment liability survives, as it arises ex lege). Not delictually/criminally accountable; a curator ad litem litigates. Validity is judged at the moment of the act — invalid unless done in a lucidum intervallum.
Types of curator
- Curator BONIS — property / estate
- Curator AD LITEM — litigation
- Curator PERSONAE — the person / welfare
Statutory frame
The Mental Health Care Act 17 of 2002 regulates the care, treatment, rehabilitation and administration of the estates of mental health care users — balancing protection with dignity and autonomy (Constitution s 9, s 10, s 12). A person who marries because delusional 'voices' command it has understood the act, but the marriage is void — the motivation rested on delusion.
Key Rule
Mental illness: contracts VOID (enrichment may survive); curator ad litem litigates. Lange: delusion-motivated acts are incapable even if understood. VOID at the moment, unless LUCID.
Leading Cases
Lange v Lange1945 AD 332Mental illness extends to acts the person understands but is motivated to perform by delusions.
Facts. A spouse sought to set aside a juristic act on the basis of the other's mental illness, even though that person appeared to understand the act.
Legal question. Is a person mentally ill where they understand an act but are motivated to perform it by delusions?
Judgment. The act was held invalid for want of capacity on the delusion ground.
Significance. Expanded the cognitive test (Pheasant) by adding the volitional limb — even apparent understanding is irrelevant if an insane delusion drove the decision.
Exam tip. Even apparent understanding doesn't save an act driven by delusion. Apply both Pheasant (cognitive) and Lange (volitional) in every mental-illness capacity question.
Pienaar v Pienaar's Curator1930 OPD 171A declared mentally-ill person under curatorship is not automatically deprived of all capacity — they retain it to the extent they are de facto (lucidly) capable at the time.
Facts. A person had been declared incapable of managing their affairs and a curator had been appointed to the estate; the question was whether the person retained any capacity to act.
Legal question. Does a declaration of mental illness and the appointment of a curator strip the person of all capacity to act?
Judgment. De Villiers JP held that such a person retains the right to contract and deal with property to the extent they are de facto capable of doing so.
Significance. Confirms that capacity can fluctuate — curatorship gives assistance where needed; it is not a blanket removal of capacity.
Exam tip. Curatorship is not total incapacity — ask whether the person was in fact lucid/capable at the moment of the act.
Intoxication
The Tavern
The test
Intoxication (alcohol or any drug) limits capacity only when severe — the person must be non compos mentis, with not even the faintest notion of contracting or its terms. Mere persuadability is not enough.
Van Metzinger — VOID, not voidable
Drunkenness must destroy the reason (Rumpff J). In SA law the contract is VOID; in English law it is merely voidable. Never say 'voidable' for SA intoxication.
Key Rule
Intoxication must render the person non compos mentis (Van Metzinger). The contract is VOID in SA (not voidable as in English law).
Leading Cases
Van Metzinger v Badenhorst1953 (3) SA 291 (T)Intoxication test — non compos mentis; the drunken contract is VOID in SA, not voidable.
Facts. A contract was concluded by a party who was severely intoxicated at the time.
Legal question. What degree of intoxication voids a contract, and is the contract void or voidable in SA?
Judgment. Rumpff J held the SA position to be voidness where the party was non compos mentis.
Significance. The leading SA intoxication authority and the SA/English divergence. The threshold is destruction of reason — not merely impairment.
Exam tip. Never say 'voidable' for SA intoxication — it is VOID. The threshold is very high: complete destruction of reason.
Common Mistake
Saying 'voidable' for SA intoxication. SA follows the void rule.
Prodigality
The Spendthrift's Court
A spendthrift — but only once a court says so.
Definition
A prodigal has normal mental ability but, through a defect of character or judgment, recklessly squanders assets toward destitution. Prodigality per se does not affect capacity.
Court order required
- DECLARE the person a prodigal
- INTERDICT limiting capacity over the estate
- Appoint a CURATOR BONIS
Phil Morkel — VOIDABLE
A prodigal's contractual capacity is treated like a minor's, not a mentally ill person's. So an unassisted contract is VOIDABLE and the curator bonis may ratify it — unlike mental illness, where it is void and unratifiable.
Key Rule
No effect until a court declares + interdicts + appoints a curator bonis. The prodigal is treated like a minor — contracts VOIDABLE and ratifiable (Phil Morkel). Fully accountable in delict/crime.
Leading Cases
Phil Morkel Bpk v Niemand1970 (3) SA 455 (C)A prodigal's contracts are voidable (like a minor's) and ratifiable by the curator bonis — distinct from a mentally ill person's void contracts.
Facts. A declared prodigal concluded a contract; the question was its validity and whether the curator could ratify.
Legal question. Is a prodigal's unassisted contract void or voidable?
Judgment. Van Winsen J treated the prodigal like a minor; the contract was voidable and ratifiable.
Significance. The crucial distinction from mental illness (void, unratifiable).
Exam tip. Prodigal = like a minor (voidable, ratifiable); mentally ill = void, unratifiable.
Common Mistake
Treating a prodigal's contract as VOID. After Phil Morkel it is VOIDABLE.
Insolvency
The Sequestrated Estate
Power over the estate only
Sequestration under the Insolvency Act 24 of 1936 is required first. The insolvent retains full personal capacity; only power over the estate is limited.
s 23(2) — Insolvency Act 24 of 1936
A contract by the insolvent is valid provided it
(1) does not dispose of estate property and
(2) is not likely to harm the estate. Disqualifications attach (e.g. cannot be a company director until rehabilitation).
Litigate & accountability
The insolvent may sue/be sued in status and non-estate matters without the trustee (divorce is the paradigm). Insolvency does not affect delictual/criminal accountability.
Key Rule
Sequestration limits power over the ESTATE only (s 23(2) of the Insolvency Act 24 of 1936). Personal capacity, status litigation and accountability are retained.
Common Mistake
Treating insolvency as removing personal capacity. It limits estate power only.
Physical disability
The Enabling Hall
No reduction of capacity
Physical illness or disability, on its own, does not reduce capacity to act, to litigate or to be accountable. The law's role is to enable the person to express their will — interpreters, sign language, assistive technology.
When a curator helps
Where a person cannot manage their affairs, a curator bonis may assist with administration. Only where an illness also impairs mental functioning do the mental-capacity rules apply. Disability is a listed s 9 ground under the Constitution.
Key Rule
Physical disability does not in itself limit capacity — the law is enabling. A curator bonis may assist with administration if needed.
Common Mistake
Reducing capacity on the basis of physical disability alone. The law is enabling, not paternalistic.
Comparison
The Comparison Wall
Void vs voidable vs retained — at a glance.
The wall
- Mental illness — contracts VOID; curator ad litem; not accountable
- Intoxication — VOID (non compos mentis); none for the duration
- Prodigality — VOIDABLE & ratifiable (court order); fully accountable
- Insolvency — estate power limited (s 23(2) Insolvency Act 24 of 1936); fully accountable
- Physical disability — full capacity retained; curator bonis to assist
Key Rule
VOID: mental illness & intoxication. VOIDABLE: prodigality (court order). Retained: insolvency (estate only) & physical disability.