One feature of the traditional Chinese criminal procedure is that it was an inquisitorial system where the judge, usually the district magistrate, conducts the public investigation of a crime.
The laws of the aristocratic societies of early China put substantial emphasis on maintaining distinct ranks and orders amongst the nobles, in addition to controlling the populace.
The early rulers of the Zhou dynasty issued or enforced laws that already exemplified the values of a primogeniture regime, most notable of which is filial piety.
The earliest document on the law in China that is generally regarded as authentic is the Kang Gao (康誥), a set of instructions issued by King Wu of Zhou to a younger prince for the government of a fief.
During the 6th century BC, several of the independent states into which the Zhou kingdom had fragmented codified their penal laws and inscribed them on bronze cauldrons.
One of the reasons for its success was the adoption, on the advice of Lord Shang Yang, of far-reaching penal and administrative codes in the 4th century BC.
During this stage, law was marked by a purely Legalist spirit, hostile to the moral values advocated by the Confucian school of thought.
The Legalist school, as represented by such thinkers as Han Fei Zi, insisted that the ruler must always rely on penal law and the imposition of heavy punishments as the main instrument of the government.
On the question of legislative technique, the Legalists stressed that the rules enacted by the ruler for punishment of offences should be clear and intelligible to the ordinary people, and they should be properly communicated to the populace.
Multiple corporal punishments were implemented by the Qin, such as death by boiling, chariots, beating, and permanent mutilation in the form of tattooing and castration.
It was recognised that there was a need for complex penal and administrative codes that enabled the emperor to govern the country through a hierarchy of ministers and officials, all ultimately responsible to him.
Imperial legal systems all retained the original Legalist insistence that the powers of officials be defined in detail and that punishments be prescribed for transgressions, whether inadvertent or not.
By the time of the Qing dynasty however, the mass of legislation had increased to such an extent that it was doubtful whether even officials could adequately master the complex distinctions it came to contain.
The complexity of the Chinese administrative system has made it difficult for Western students to acquire a general familiarity with the legal principles that govern it.
The study of unofficial law has also been limited due in part to the fact that the data are contained in such a variety of source materials, most extremely difficult to access.
The lack of access to source material gave earlier scholars, both Chinese and Western, the mistaken impression that Imperial China did not have a system of civil law.
The practice grew extensively under the Qing, with the result that, by the end of the 19th century, the penal code had lost something of its internal coherence and become an unwieldy instrument.
Jean Escarra, has suggested that the penal law as a whole was intended to function as a guide to model conduct and not as a set of enforceable rules.
Whilst this view has largely been rejected, it is clear that many of the enforced rules on family relationships were retained on account of their symbolic value.
From the provisions of the penal code, magistrates could either derive principles of civil law either directly, if a matter was stated in the penal code (such as matters regarding debt and usury, dealings with land, the borrowing and pledging of property, and the sale of goods in markets), or indirectly reading into a criminal statute a basis for a private civil suit.
Moreover, scholars in the early 21st century, such as Philip Huang (黃宗智), have argued that the traditional Chinese system of justice was fair, efficient, and frequently used in the settlement of disputes.
From the Sui dynasty onwards, women could not hold property directly and, for land to stay in the same family, it had to pass between male heirs following the rule of primogeniture.
During the Qin and Han, local magistrates were fully authorised to apply the full scale of punishments, including the death penalty.
Whenever a sentence of greater severity than a beating was applicable, it was necessary to forward the case to the next superior court in the hierarchy, that of the prefect, for rehearing.
Encouragement of the virtue of filial piety helped to strengthen the related duty of respect and submission to imperial authority.
The codes signal their moral orientation by placing right at the beginning of the "General Principles" section a description of the offences known as the "Ten Abominations".
As the official commentary of the Qing code states: "persons guilty of any of the Ten Abominations destroy human bonds (倫), rebel against Heaven (天), go against reason (理), and violate justice (義)."