THE CATEGORIES OF INCAPACITY
If the claimant’s incapacity can constitute a ground of restitution it is vital to determine what constitutes incapacity for these purposes. A number of different types of incapacity can be identified which need to be analysed with some care since there is a great deal of uncertainty, both as to the requirements for establishing each type of incapacity and as to the effect of each type on the restitutionary claim.
(A) MENTAL INCAPACITY
Mental incapacity is defined as where a person is unable to make a decision for him or herself because of an ‘impairment of, or a disturbance in the functioning of, the mind or brain’, which may be permanent or temporary. It covers a wide variety of conditions including people whose mental development has been slow, whose brains have been damaged or who suffer from some type of recognized physical illness, such as the effects of a brain tumour, or psychological condition, such as schizophrenia or senile dementia. Whatever the type of mental incapacity, whether the claimant can be considered to be incapacitated is a question of degree. The fact that a claimant suffers a mental condition may be relevant to restitutionary claims in four different circumstances.
-  Meaning that the person is unable to understand, retain, or weigh information relating to a decision or tocommunicate a decision: Mental Capacity Act 2005, s 3(1).
-  Ibid, s 2(1). 3 Ibid, s 2(2). 4 Simpson v Simpson  Fam Law 20.
-  13 Re Beaney  1 WLR 770. 14 Mental Capacity Act 2005, s 16(2).
-  15 Re Walker  1 Ch 160. 16 Baldwyn v Smith  1 Ch 588.
-  17 See p 196, above.