A judge, or arbiter of justice, is a lead official who presides over a court of law, either alone or as part of a panel of judges. The powers, functions, method of appointment, discipline, and training of judges vary widely across different jurisdictions. The judge is like an umpire in a game and conducts the trial impartially and in an open court. The judge hears all the witnesses and any other evidence presented by the parties of the case and then issues a ruling on the matter at hand. In some jurisdictions, the judge's powers may be shared with a jury.

Symbols of office

Being a judge is usually a prestigious and solemn position in society. A variety of traditions have become associated with the occupation.

In many parts of the world, judges wear long robes (usually in black or red) and sit on an elevated platform during trials (known as the bench).

In some countries, especially in the Commonwealth of Nations, judges sometimes wear wigs. The long wig often associated with judges is now reserved for ceremonial occasions, although it was part of the standard attire in previous centuries. A short wig resembling but not identical to a barrister's wig would be worn in court. This tradition, however, is being phased out in Britain in non-criminal courts.

American judges frequently wear black robes. American judges have ceremonial gavels, although American judges have court deputies or bailiffs and "contempt of court" power as their main devices to maintain decorum in the courtroom. However, in some Western states, like California, judges did not always wear robes and instead wore everyday clothing. Today, some members of state supreme courts, such as the Maryland Court of Appeals wear distinct dress.

In Italy both judges and lawyers wear particular black robes.

In the People's Republic of China, judges wore regular street clothes until 1984, when they began to wear military-style uniforms, which were intended to demonstrate authority. These uniforms were replaced in 2000 by black robes similar to those worn in the rest of the world.

In Oman, the judge wears a long stripe (Red, Green and White), while the attorneys wear the black gown.

United States

The justices of the supreme courts usually hold higher offices than the justice of the peace, a judge who holds police court in some jurisdictions and who typically tries small claims and misdemeanors. However, the state of New York inverts the usual order, with the Supreme Court of the State of New York being the most important trial court, and the Court of Appeals being the highest court; thus, New York trial judges are called "justices", while the judges on the Court of Appeals are "judges". New York judges who deal with guardianships, trusts and estates are known as "surrogates".