This book deals with criminal or penal law (I will use both terms indiscriminately), the body of law that regulates the power of the state to inflict punishment, i.e. suffering, on persons in order to enforce compliance with certain rules. Such rules typically protect public interests and values that society regards as crucial, even if the immediate interest that is protected is a private one. A case in point is theft. Many societies make the violation of private property rights a punishable offence, although the interests harmed by such violations are in the first place private ones. However, these societies regard the protection of property as essential for the social order and protect it by stronger remedies than those available under private law. The interests protected by penal sanctions vary from society to society. In some societies sexual acts between consenting adults are of no concern to the authorities, whereas in others the rules regulating sexual contact are regarded as so crucial for the maintenance of social order that violations are severely punished. The same is true, for instance, with regard to the consumption of alcohol and other psychotropic substances. Criminal laws, therefore, give an insight into what a society and its rulers regard as its core values.

Islamic law does not conform to the notion of law as found, for example, in common law or civil law systems.