Commission of the peace

A justice of the peace (JP) is a judicial officer, of a lower or puisne court, elected or appointed by means of a commission (letters patent) to keep the peace. In past centuries the term commissioner of the peace was often used with the same meaning. Depending on the jurisdiction, such justices dispense summary justice or merely deal with local administrative applications in common law jurisdictions. Justices of the peace are appointed or elected from the citizens of the jurisdiction in which they serve, and are (or were) usually not required to have any formal legal education in order to qualify for the office. Some jurisdictions have varying forms of training for JPs.

In 1195, Richard I ("the Lionheart") of England and his Minister Hubert Walter commissioned certain knights to preserve the peace in unruly areas. They were responsible to the King for ensuring that the law was upheld and preserving the "King's peace". Therefore, they were known as "keepers of the peace".

An act of 1327 had referred to "good and lawful men" to be appointed in every county in the land to "guard the peace"; such individuals were first referred to as conservators of the peace, or wardens of the peace. The title justice of the peace derives from 1361, in the reign of Edward III. The "peace" to be guarded is the sovereign's, the maintenance of which is the duty of the Crown under the royal prerogative. Justices of the peace still use the power conferred or re-conferred on them since 1361 to bind over unruly persons "to be of good behaviour". The bind over is not a punishment, but a preventive measure, intended to ensure that people thought likely to offend will not do so. The justices' alternative title of "magistrate" dates from the 16th century, although the word had been in use centuries earlier to describe some legal officials of Roman times.

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