Case Law Legal Definition: The entire collection of published legal decisions of the courts which, because of stare decisis, contributes a large part of the legal rules which apply in modern society. The entire collection of published legal decisions of the courts which, because of stare decisis, contributes a large part of the legal rules which apply in modern society. If a rule of law cannot be found in written laws, lawyers will often say that it is a rule to be found in "case law". In other words, the rule is not in the statute books but can be found as a principle of law established by a judge in some recorded case. The word jurisprudence has become synonymous for case law. Unless otherwise noted, this page was written by Lloyd Duhaime of Duhaime.org Always looking up definitions? Save time with our search provider (modern browsers only) If you find an error or omission in Duhaime's Law Dictionary, or if you have suggestion for a legal term, we'd love to hear from you!