The main principle of a dual court system is that it gets support of two legal systems: one at the local level and the other at the national. This type of court system is spread in the USA and Australia. There are such opinions that it is due to the legal system that these two nations managed to prosper for such a long time. In the aforementioned countries, the state court system provides support and ensures enforcement for the local law, whereas the federal, or national, court ensures national law enforcement. Still, the two systems overlap in their functioning as it is natural that their common range of operation is the same nation.
In the legal systems of both the USA and Australia, there is a federal law that applies to the entire country. In other words, mostly it is the federal legal system that mainly implements and supports constitutional directives. At the state level, every government is authorized to devise local laws for the citizens. As a rule, federal laws have minimal influence while states are authorized to adapt laws to ensure that people are better served.
One of the main reasons why dual court systems exist is that they aim to ensure freedom and autonomy to the state governments and make sure that there is control on the local judiciary. The Unites States and Australia are large countries, and the delegation of administrative and judicial tasks that takes place there demonstrates that the needs of various people differ. The national legal system guarantees that a state does not legislate beyond the authorized norms and standards.
The highest court of the USA is called the Supreme Court, while in Australia it is named as the High Court. The dual court system makes sure that the state and federal judiciary powers are brought together.