Any individual who has the power of a public civil officer or inferior judicial officer, such as a JUSTICE OF THE PEACE.
The various state judicial systems provide for judicial officers who are often called magistrates, justices of the peace, or police justices. The authority of these officials is restricted by statute, and jurisdiction is commonly limited to the county in which the official presides. The position may be elected or appointed, depending on the governing state statute. The exact role of the official varies by state; it may include handling hearings regarding violations of motor vehicle codes or breaches of the peace, presiding over criminal preliminary hearings, officiating marriages, and dispensing civil actions involving small sums of money.
U.S. magistrates are judicial officers appointed by the judges of federal district courts pursuant to the United States Magistrates Act (28 U.S.C.A. §§ 631 et seq.), enacted in 1968. This act was designed to reduce the workload of federal courts by replacing the old system of U.S. commissioners with a new system of U.S. magistrates. U.S. magistrates can perform more judicial functions than could U.S. commissioners. Federal magistrates may be assigned some, but not all, of the duties of a federal judge. They may serve as special masters (persons appointed by the court to carry out a particular judicial function on behalf of the court), supervise pretrial or discovery proceedings, and provide preliminary consideration of petitions for postconviction relief. U.S. magistrates generally may not decide motions to dismiss or motions for SUMMARY JUDGMENT, because these motions involve ultimate decision making, a responsibility and duty of the federal courts. However, if all the parties to a case agree, a federal magistrate may decide such motions and may even conduct a civil or misdemeanor criminal trial. Federal magistrates are not permitted to preside over felony trials or over jury selection in felony cases.