To understand why we use case law, you need to understand what it means. A court of law is a place where judges make decisions that affect the rights and responsibilities of the citizens.
A court makes its own decisions based on the laws, and those decisions are binding on all citizens. For example, a judge may have made a ruling on a case that a person had committed a crime. That decision would be binding on all of the citizens. Common law is based on these decisions that have been made by the courts.
There are many different types of legal precedents. Common law comes from cases in which there are no written laws. These are based on rulings from the people and the courts. The people of MATRIMONIAL LAW America, in particular, base their system on common law, which is known as case law. In most countries, the case law is the basis of law. The United States is unusual in that it is unique in the world in that it is the only country in the world that uses case law to create a legal system.
The main difference between statutory law and common law is that common law is an independent body of law that stands above the law made by statute. Most countries have two separate kinds of law: statutory and common.