Examining and Identifying the Similarities and Differences among the Rules Governing Contractual Fault in Iranian Law, Imamiyyah Jurisprudence, English Law, American Law, and French Law

Contractual fault is one of the important issues in the law of obligations and plays a fundamental role in determining the liability of the obligor in cases of non-performance of an obligation. In different legal systems, despite the acceptance of the principle of the binding force of contracts and the necessity of performance, differences can be observed in the foundations, conditions of realization, and legal effects of contractual fault. In Iranian law, which is influenced by Imamiyyah jurisprudence and French law, the element of fault plays an important role in establishing contractual liability, whereas in common law systems, particularly English and American law, contractual liability is more often analyzed on the basis of the mere breach of contract. In Iranian law, the general principle is that once the due date has arrived and the obligation has not been performed, a claim for damages becomes possible; however, in certain cases, even before maturity, where impossibility of performance or lack of intention to perform is established, anticipatory breach may be invoked. The common foundation among Iranian law, Imamiyyah jurisprudence, and, to some extent, French law is the emphasis on compensating damages in such a way that the injured party is placed in the hypothetical position that would have existed had the contract been fully performed. In Iranian law and Imamiyyah jurisprudence, conditions such as the occurrence of damage, causal relationship, certainty, and foreseeability of damages are taken into consideration, although these conditions are set out in Iranian legislation in a scattered manner and are further elaborated in legal doctrine. French law, which has influenced Iranian law, also adopts a similar approach to full compensation for damages. By contrast, English law presents more coherent and clearly defined limitations, such as remoteness of damage, the doctrine of mitigation of damages, contributory fault of the injured party, and force majeure. American law, in addition to accepting the basis of fault, also considers its different degrees and adjusts the scope of liability according to the severity of fault. An important point of divergence is that, in Iranian law, the degree of fault does not affect the extent of liability, whereas in American law this factor is determinative. Furthermore, in Iranian law, force majeure has an explicit statutory basis, while other limitations are mostly discussed in legal doctrine, unlike common law systems, which provide more precise frameworks.