In the English law, justices of the peace are "judges of record appointed by the king's commission to be justices within certain limits, for the conservation of the peace and the execution of divers things comprehended within their commission and within divers statutes committed to their charge." Before the institution of this office there existed in England by the common law certain officers appointed for the maintenance of good order, and called conservatores pacis, keepers of the peace. Some of them exercised their functions by virtue of their tenures, and some by virtue of their offices; others were chosen by the freeholders of their counties. The period at which this office ceased, and justices of the peace were first created, has been disputed; but the better opinion seems to fix it at the beginning of the reign of Edward III. At that time the new king, fearing that some risings or other disturbances might take place in protest against the manner of his accession to the crown, sent writs to all the sheriffs in England commanding that peace be kept throughout their bailiwicks on pain and peril of disinheritance and loss of life and limb; and in a few weeks after the date of these writs it was ordained in parliament that, for the better maintaining and keeping of the peace in every county, good men and lawful which were no maintainers of evil or barrators in the county should be assigned to keep the peace. (Black. Com., i. 350.) From that time the election of the conservators of the peace was taken from the people, and their creation resided thenceforth in the assignment of the crown.

It was only, however, by subsequent statutes that the conservators of the peace acquired a judicial character and functions. By 4 Edward III. c. 2, they were empowered to "take indictment," and by 34 Edward III. c. 2, they were commissioned to "hear and determine" in cases of felonies and trespasses. It is probable that not until then were these officers called justices. The office, as constituted and defined by these and later statutes, occupies an important place in the English judicial system. It was adopted in the several states of this country at their settlement, and may be considered to possess here the general character and functions allowed to it in England by force of statutes. But it is to be remarked that in all the states legislative enactments have so fully enumerated the powers and duties of justices of the peace, both in civil and criminal affairs, as perhaps to preclude reference to the English law on the subject. - Justices of the peace are in some states elected by the people, and in others receive their appointment from the executive. Their jurisdiction is determined by their commissions and the provisions of various statutes. These are to be strictly construed, and no authority can be implied.

Without attempting a recital of all the particular functions exercised by these officers, it will suffice for our present purpose to mention, under their criminal jurisdiction, that when they are not limited by the existence of special courts, they possess still their ancient common law powers as conservators of the peace, and as such may suppress riots and affrays and apprehend all disturbers of the peace. Then they may punish them by fine, and take recognizances for their future good behavior. By virtue of their criminal authority they may also issue their warrants for the arrest of offenders. If the offence be a trifling one, they may themselves determine in the matter. If, however, it be of an aggravated nature, they commit or bind over the criminal for trial in a regular court. They may judge in civil suits when but a small amount is involved, but not generally in cases of libel, slander, or malicious prosecution, or when title to real property comes in question. As further examples of their usual powers, it may be added that they may issue summonses for witnesses to appear in their own courts, and to answer in civil suits pending before other courts; they may administer oaths in all cases in which an oath is required; they may celebrate marriages; and may make examinations and issue warrants in cases of bastardy.

They also exercise certain functions under the poor laws. The justice must have jurisdiction of the parties and of the matter, or his interference is a trespass. But when he acts within his jurisdiction and by color of his office, he is responsible in a civil suit only when he has acted from corrupt or malicious motives. He may be impeached, and in some states removed by petition and hearing of the charges made against him before a higher court. A justice must keep a record of his proceedings, and may adjourn his court from day to day. The pleadings before him are, for the benefit of suitors, treated with great liberality. - In the decree for the reorganization of the judicial system of France (Aug. 24, 1790) juges de paix were created in imitation of the English officers of the same name. They were to decide summarily, without expense to suitors and without the intervention of counsel, affairs of slight importance, and especially those which involved disputed facts rather than contested points of law. The decree of September, 1791, concerning criminal procedure, invested the juges de paix with police functions; at a later period they were called to the presidency of those police tribunals which took cognizance of minor offences.

Under the law of May 25, 1838, the French justices are empowered to decide finally in all causes purely personal, and involving no more than 100 francs, but subject to appeal in all such causes involving from 100 to 200 francs. With similar limitations they have jurisdiction in actions between landlords and tenants; in suits for damages to fields, fruits, and harvests; between laborers and their employers, and between servants or apprentices and their masters; and in civil suits for verbal defamation, and in those breaches of the peace and assaults which are not expressly provided for in the criminal law. Their decrees are subject to appeal in all possessory actions, in cases involving questions of boundaries, and in those arising out of the use of mill privileges and streams applied to irrigation. As officers of the judicial police and auxiliary to the prosecuting officer of the government (procureur du roi), they receive informations and make examinations into charges of flagrant crime committed within their jurisdiction.