An individual’s power of testamentary disposition is basically limited to one-third of his or her net estate (i.e., the assets remaining after the payment of funeral expenses and debts). Two-thirds of the estate passes to the legal heirs of the deceased under the compulsory rules of inheritance.

There is a fundamental divergence between the Sunni and Shiʿi schemes of inheritance. Sunni law is essentially a system of inheritance by male agnate relatives, or ʿaṣabah—i.e., relatives who, if they are more than one degree removed from the deceased, trace their connection to the deceased through male links. Among the ʿaṣabah, priority is determined by: (1) class, with descendants excluding ascendants, who in turn exclude brothers and their issue, who in turn exclude uncles and their issue; (2) degree, with relatives nearer in degree to the deceased excluding the more remote within each class; and (3) strength of blood ties, with germane, or full-blood, connections excluding consanguine, or half-blood, connections among collateral relatives. This agnatic system is mitigated by allowing surviving spouses and a limited number of females and nonagnates—daughters; sons’ daughters; mothers; grandmothers; germane, consanguine, and uterine sisters; and uterine brothers—to inherit a fixed fractional portion of the estate in certain circumstances. But the females among these relatives receive only half the share of the male relatives of the same class, degree, and blood tie, and no female excludes from inheritance any male agnate, however remote. No other female or nonagnatic relative has any right of inheritance in the presence of a male agnate. If, for example, the deceased is survived by his wife, his daughter’s son, and a distant agnatic cousin, the wife will be restricted to one-fourth of the inheritance, the grandson will be excluded altogether, and the cousin will inherit three-fourths of the estate.

Shiʿi law rejects the criterion of the agnatic tie and regards both maternal and paternal connections as equally strong grounds of inheritance. In the Shiʿi system, as in Sunni law, the surviving spouse always inherits a fixed portion, but all other relatives, including females and nonagnates, are divided into three classes: (1) parents and lineal descendants; (2) grandparents, brothers and sisters, and their issue; and (3) uncles and aunts and their issue. Any relative of class 1 excludes any relative of class 2, who in turn excludes any relative of class 3. Within each class, the nearer in degree excludes the more remote, and the full-blood excludes the half-blood. While, therefore, a male relative normally takes double the share of the corresponding female relative, females and nonagnates are much more favourably treated in Shiʿi law than they are in Sunni law. In the case mentioned above, the wife would receive one-fourth, but the remaining three-fourths would go to the daughter’s son, or indeed to the daughter’s daughter, and not to the agnatic cousin.

Under Shiʿi law the only restriction upon testamentary power is the one-third rule, whereas Sunni law does not allow any bequest in favour of a legal heir. Under both systems, however, bequests that infringe these rules are not necessarily void and ineffective; when testators have acted beyond their powers, the bequests may still be ratified by the legal heirs. Further protection is afforded to the rights of the legal heirs by the doctrine of death sickness. Any gifts made by a dying person in contemplation of death are subject to precisely the same limitations as bequests and, if they exceed these limits, will be effective only with the consent of the legal heirs.

Procedure and evidence

Traditionally, sharia law was administered by the court of a single qadi, who was the judge of the facts as well as the law, although on difficult legal issues he might seek the advice of a professional jurist or jurisconsult (mufti). There was no hierarchy of courts and no organized system of appeals. Through his clerk (kātib), the qadi controlled court procedure, which was normally characterized by a lack of ceremony or sophistication. Legal representation was not unknown, but the parties would usually appear in person and address their pleas orally to the qadi.

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The first task of the qadi was to decide which party bore the burden of proof. This was not necessarily the party who brought the suit; rather, it was the party whose contention was contrary to the initial legal presumption applying to the case. In the case of an alleged criminal offense, the relevant presumption was the innocence of the accused, and, in a suit for debt, the presumption was that the alleged debtor was free from debt. Hence, the burden of proof would rest upon the prosecution in the first case and upon the claiming creditor in the second. The burden of proof might of course shift between the parties several times during the same suit—for example, when an alleged debtor would plead a counterclaim against the creditor.

The standard of proof required—whether on an initial, intermediate, or final issue—was rigid and basically the same in both criminal and civil cases. In the absence of a confession or an admission by the defendant, the plaintiff or prosecutor was required to produce two witnesses to testify orally to their direct knowledge of the truth of his contention. Written evidence and circumstantial evidence, even of the most compelling kind, were normally inadmissible. Moreover, the oral testimony (shahādah) usually had to be given by two male adult Muslims of established integrity and character. In certain cases, however, the testimony of women was acceptable (two women being required in place of one man), and, in most claims of property, the plaintiff could satisfy the burden of proof through one witness and his own solemn oath as to the truth of his claim.

If the plaintiff or prosecutor produced the required degree of proof, judgment would be given in his favour. If he failed to produce any substantial evidence at all, judgment would be given in the defendant’s favour. If he produced some evidence but the evidence did not fulfill the strict requirements of shahādah, the defendant would be offered the oath of denial. Properly sworn, this oath would secure judgment in his favour; but if he refused it, judgment would be given in the plaintiff’s favour, provided, in some cases, that the latter himself would swear an oath.

In sum, the traditional system of procedure was largely self-operating. After his initial decision as to the incidence of the burden of proof, the qadi merely presided over the predetermined process of the law: witnesses were or were not produced; the oath was or was not administered and sworn; and the verdict followed automatically. This formalistic law of evidence was not, however, universally held. Dissenting jurists, such as the influential 14th-century Ḥanbalī scholar Ibn Taymiyyah, believed that any type of evidence, including circumstantial evidence and the testimony of any witness, was admissible to help the qadi reach the correct decision.