Hi, from what I know, Chinese laws are a mixture of civil law and socialist law . The Australian legal system is based on a fundamental belief in the rule of law, justice and the independence of the judiciary. All people—Australians and non-Australians alike—are treated equally before the law and safeguards exist to ensure that people are not treated arbitrarily or unfairly by governments or officials. Principles such as procedural fairness, judicial precedent and the separation of powers are fundamental to Australia’s legal system. The common law system, as developed in the United Kingdom, forms the basis of Australian laws. It is distinct from the civil law systems that operate in Europe, South America and Japan, which are derived from Roman law. Other countries that employ variations of the common law system are the United States, Canada, New Zealand, Malaysia and India.

The UK does have a constitution its based around parliamentary sovereignty and the rule of law. The problem is that this is not stated in a single document but littered across a number of judgements, treatises and conventions that came out organically from the practice of our ruling house. We ceased to be an absolutist monarchy after we impeached and beheaded Charles I in 1640's. So after the restoration of his son in 1658 as a figure head we have had the same system in place, which means we have produced one of the most stable political systems in modern times, and were probably the longest uninterrupted liberal democracy there is. The idea of the rule of law, (in theory) is that unless you break the law you are not supposed to have your freedom restricted. If you do break the law you are then entitled to a fair trial, and this entire process is supposed to be transparent and based legality, not the judgement of the ruling power of the time, hence the separation of power. Existing laws can change through legal precedents, which would come out of judgements from our higher courts. Otherwise the elected members of parliament can try and pass laws through the House of Commons and this legislation is then passed on to a second house called the House of Lords, which is composed of unelected peers (landed gentry, prominent citizens etc.) who amend or reject the proposed law of the House of Commons. The House of Lords as come under alot of criticism in recent time and generally our system compared to other Europeans and the rest of the English speaking world is more set by pomp and tradition.