Foreign, Comparative, and International Law: Legal Systems

In Common Law systems, judicial opinions take precedence over other types of laws, including legislation. The United States government and 49 out of 50 states are Common Law jurisdictions. The U.S. inherited its Common Law tradition from the United Kingdom, just like many other former and current British protectorates and colonies.

Some of the key features of Common Law systems are the following:

• There may not be codified laws or a written constitution (like the U.K.).
• Judicial decisions are binding. An opinion of the highest court can only be overturned by the same high court, or through an act of the legislature.
• Extensive freedom of contract - few provisions are implied into the contract by law (although provisions seeking to protect private consumers may be implied).
• Generally, everything is permitted that is not expressly prohibited by law.

In Civil Law jurisdictions, the primary source of law is a written code.

Features of a civil law system include:

• A written constitution based on specific codes (e.g., civil code, codes on administrative law, tax law, constitutional law) which establishes basic rights and duties. Administrative law is usually less codified; administrative court judges tend to behave more like common law judges.
• Legislative acts (not judicial opinions) are considered binding for all. Judge-made law is not a central focus in civil, criminal and commercial courts. Judges do tend to follow previous judicial decisions, while constitutional and administrative courts can nullify laws and regulations, and their decisions in such cases are binding for all.
• The writings of legal scholars may have significant influence on the courts (e.g., in Germany).
• Courts are specific to the underlying codes. This means there are separate constitutional court, administrative court, and civil court systems that opine on consistency of legislation and administrative acts with and interpret that specific code.
• Less freedom of contract than in Common Law systems. Many provisions are implied into a contract by law and parties cannot contract out of certain provisions.

Beyond Civil and Common

The two major legal systems in the world are Civil Law and Common Law, but JurisGlobe, a project of the University of Ottawa, identifies five categories of legal systems: Civil law, Common law, Customary law, Muslim law and Mixed law systems.

In Mixed law systems, either two or more systems apply cumulatively or interactively, or different systems are applied depending on the legal issue. For example, Civil law controls property, contracts, and family law in Louisiana, while the Common law principles of jury trials, burdens of proof, and pretrial discovery still operate in the state's criminal law. A legal structure with competing or overlapping legal systems is known as "polycentric law"

Only a Starting Point

It is important to recognize that two jurisdictions with the "same" legal system may still be significantly different in reality. For example, the U.S. and the U.K. are both Common Law jurisdictions, but one has a president and a written Constitution while the other has a monarch, a prime minister, and an unwritten constitution.