Magistrates are a little less common in the United States than in Europe, but the position does exists in some jurisdiction. In the United States federal court system, magistrates are appointed by life-term federal District Judges, to serve a term of eight years. Magistrate judges are concerned with lesser criminal cases and certain classes of civil cases. Felonies are handled by the District Judges, as are civil jury trials unless all of the parties to the case agree that the Magistrate can preside over the case. Magistrates didn't exist in U.S. federal courts until 1968, when the position was created to allow District Judges to focus on major cases, allowing lesser matters to be handled by the magistrate. The system has worked well in the last 30 years, shifting the caseload to the desired balance. This system was modeled after European systems, and most other countries have similar duties for magistrates. There are other, more specific types of magistrates, but this term is used to broadly describe this level of authority.
In many state judicial systems of the United States, magistrate's courts are the successor to justice of the peace courts, and frequently have authority to handle the trial of civil cases up to a certain amount, applications for bail, arrest and search warrants, and the adjudication of petty criminal offenses.
In China
Magistrate, or chief magistrate, is also a common Chinese translation of xianzhang (縣長 "county leader") the political head of a county. The translation dates from imperial China in which the county magistrate was the lowest official in the imperial Chinese bureaucracy and had judicial in addition to administrative functions.
On Taiwan, the county magistrate elections are heavily and sometimes bitterly contested and are often a stepping stone to higher office. County magistrate elections were first open to election in the 1960s and before the end of martial law in 1991, they were the highest elected position of any real power and hence were the focus of election campaigned by the dangwai movement.
In Mainland China, the county magistrate is technically elected by the local people's congress but in fact is appointed by the Communist Party. Although there have been some elections at the lower township level, these elections (with one exception which was considered irregular and illegal) have not extended up to the county level. Although not an important official, county magistrates, particular in rural areas, can sometimes have a strong impact on the life of ordinary people by enforcing central government regulations.
Etymology
Derived from Middle English word "magistrat" from Old French, from Latin "magisträtus", from magister; magistr-, meaning "master".