Common law
WordNet
noun
(1) (civil law) a law established by following earlier judicial decisions
(2) A system of jurisprudence based on judicial precedents rather than statutory laws
"Common law originated in the unwritten laws of England and was later applied in the United States"
WiktionaryText
Noun
- A law or system of laws based on judicial precedent rather than written laws; particularly the legal system of this form which originated in the United Kingdom and remains in effect in that country and in many of its former colonies and possessions.