Legal capacity is primarily divided into two types: capacity to receive or inhere rights and obligations, and capacity for the active exercise of rights and obligations. The former may be described as `receptive legal capacity', and the latter as 'active legal capacity'.
Every person in Islamic Law is endowed with legal capacity of one kind or another. Receptive legal capacity is the ability of the individual to receive rights and obligations on a limited scale, whereas active legal capacity enables him to fulfill rights and discharge obligations, to effect valid acts and transactions, and in bear full responsibility toward God and his fellow human beings.
The criterion of the existence of receptive legal capacity is life itself, whereas the criterion of active legal capacity is maturity of intellect. Receptive legal capacity is vested in every human being, competent or otherwise. An insane person, a foetus in the womb, a minor and a mentally challenged person, whether in good health or in illness: all possess legal capacity by virtue of their dignity as human beings.
Active legal capacity is only acquired upon attaining a certain level of intellectual maturity and competence. Only a person who understands his acts and his words is competent to conclude a contract, discharge an obligation, or be punished for violating the law. Active legal capacity, which is the basis of responsibility, is founded in the capacity of the mind to understand and to discern. But since intelligence and discernment are hidden qualities which are not readily apparent to the senses, the law has linked personal responsibility with the attainment of the age of puberty, which is an obvious phenomenon and can be established by factual evidence. However, it is the intellectual faculty of the individual rather than age as such which determines his legal capacity. This is why an adult who is insane, or an adult of any age who is asleep, is not held responsible for his conduct. The principle here is dearly stated in the Hadith which provides: `The pen is lifted from three persons: the one who is asleep until he wakes, the child until he attains puberty, and the insane person until he regains sanity.
Receptive legal capacity may either be 'deficient' or 'complete'. The receptive legal capacity of a child in the womb is incomplete in the sense that it can only receive certain rights, such as inheritance and bequest, but cannot bear any obligation toward others. Receptive legal capacity is complete when a person can both have rights and bear obligations. This type of legal capacity is acquired by every human being as of the moment of birth. During its infancy and later stages of childhood, a child is capable of discharging, albeit through his guardian, certain obligations in respect, for example, of maintenance, liability for loss, and payment for services rendered to him.
As for the active legal capacity, three possible situations are envisaged. First, a person may be totally lacking of active legal capacity, as in the case of a child during infancy or an insane person of any age. Since neither is endowed with the faculty of intellect, no legal consequences accrue from their words and acts. When a child or a madman kills someone or destroys the property of another person, they can only be held liable with reference to their property, but not to their persons. They cannot be subjected, for example, to retaliation, or to any other type of punishment.
Second, a person may be partially lacking in active legal capacity. Thus a discerning child, that is, a child between seven and fifteen years of age, or an a person who is mentally challenged, who is neither insane nor totally lacking in intellect but whose intellect is defective and weak, possess a legal capacity which is deficient. Both of them possess an active legal capacity which is incomplete and partial.
The discerning child and the mentally challenged person are capable only of concluding acts and transactions that are totally to their benefit, such as accepting a gift or charity, even without the permission of their guardians. But if the transaction in question is totally disadvantageous to them, such as giving a gift or making a will, or pronouncing a divorce, these are not valid at all even it their guardians happen to approve of them. As for transactions which partake in both benefit and loss, they are valid but only with the permission of the guardian, otherwise they are null and void.
Thirdly, active legal capacity is complete upon the attainment of intellectual maturity. Hence every major person who has acquired this ability is presumed to possess active legal capacity unless there is evidence to show that he or she is deficient of intellect or insane.
Persons who are fully competent may sometimes be put under interdiction with a view to protecting the rights of others. A person may be interdicted by means of a judicial order which might restrict his powers to conclude certain transactions. A debtor may thus be interdicted so that the rights of his creditors may be protected. A person in his death-illness is also deficient of legal capacity, as severe illness and fear of imminent death affect the physical and mental faculties of the individual. But ordinary illness and other conditions which do not impair the intellectual capacity of a person have no bearing on his active legal capacity.
The main source for this article was Mohammad Hashim Kamali book “Principles of Islamic Jurisprudence”.