Common Law vs. Statutory Law—What’s the Difference?

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Common Law vs. Statutory Law—What’s the Difference?

Most nations in the world follow common and statutory laws. These types of laws set a standard of acceptable behavior and justice for both citizens and their government. Learning the difference between common law and statutory law can help you better understand your rights. At Coolidge Law Firm, we help educate Arizona residents about national and state laws and ensure their rights are upheld. Continue reading to learn more about common law vs statutory law, and examples of each.

Common Law vs. Statutory Law


Common law is uncodified, meaning that it is not compiled into rules and statutes, but instead relies on precedent. The precedent is set by the historical judicial rulings of previous federal, state, or local court cases. Sometimes, judgments that establish a new precedent turn into a new law. One example of common law is a common-law marriage, which recognizes that couples who meet certain conditions have the same rights as couples who are married. 

Common law is also known as case law, which entails all the documented collections of previous case precedent. So if you’ve ever heard a lawyer argue in court that a ruling has precedent or does not have precedent according to a specific case, then they are making their argument based upon common law.

In an effort to promote stability, the precedents set by higher courts are legally binding on lower courts. When a precedent is set for a certain type of case by a higher court, then the lower court has to give the same judgment in future cases.  However, if a lower court feels the precedent is outdated or does not relate closely enough to the case at hand, then they can choose to deviate or modify the precedent.


The main difference between common law and statutory law is that common law is based on past judicial opinions, while statutory law is based on current statutes (written laws). Examples of statutory laws include traffic laws like driving on a suspended license, drug laws like those regarding drug possession, etc.

Unlike common law, statutory law is codified and encompasses compiled legislation that has been passed on a local, state or federal level. Also known as civil law, statutory law is strict in its application, which means it is not subject to the same interpretation as common law. In other words, a statute means exactly what it says.

However, statutes are subject to being overturned or changed if a later legislative body finds them unconstitutional. Some statutes are even set to expire every few years. If the law is still needed, then it can be renewed after the expiration. In this way, statutory law is flexible in order for the law to remain relevant and reasonable to the people it was designed to protect or regulate.

A Criminal Defense Attorney in Phoenix You Can Trust

Todd Coolidge, a criminal defense attorney in Phoenix, is well-versed in the differences between common law and statutory law. At Coolidge Law Firm, we know how to research case law to find precedent on behalf of our clients. If you’re in need of a criminal law specialist to handle your case, then look no further: schedule your consultation today!