- legal system where law emerges from judicial decisions and precedent rather than codified statutes
- originated in medieval England, spread through the British Empire
- core principle: stare decisis (let the decision stand), each ruling becomes binding precedent for future cases
- judge-made law: courts interpret, extend, and adapt rules through case-by-case reasoning
- adopted in the United Kingdom, United States, Canada, Australia, India, and former British colonies
- adversarial trial system: two parties present competing arguments before an impartial judge or jury
- flexible and evolutionary: adapts to new circumstances through reinterpretation
- contrast with civil law: precedent-driven vs statute-driven
- smart contracts as a form of automated common law: each execution establishes behavioral precedent on-chain
- see also constitution, international law, human rights