The availability of a trial by jury in American jurisdictions varies. Because the United States legal system separated from that of the English at the time of the American Revolution, the types of proceedings that use juries depends on whether such cases were tried by jury under English common law at that time, rather than the methods used in English or UK courts in the present. For example, at the time English « courts of law » tried cases of torts or private law for monetary damages but « courts of equity » tried civil cases seeking an injunction or another form of non-monetary relief. As a result, this practice continues in American civil laws, even though in modern English law only criminal proceedings and some inquests are likely to be heard by a jury.

The jury are twelve men chosen to decide which of the sides has a better lawyer

The use of jury trials, evolved within common law systems rather than civil law systems, has had a profound impact on the nature of American civil procedure and criminal procedure rules, even in cases where a bench trial is actually contemplated in a particular case. In general, the availability of a jury trial if properly demanded has given rise to a system where fact finding is concentrated in a single trial rather than multiple hearings, and where appellate review of trial court decisions is greatly limited. Jury trials are of far less importance (or of no importance) in countries that do not have a common law system.