A justice: a high-ranking judge.
Various equivalent medieval offices elsewhere in Europe.
A Chief Justiciar: the highest political and judicial officer of the Kingdom of England in the 12th and 13th centuries.
A high-ranking judicial officer of medieval England or Scotland.
A justiciary: a believer in the doctrine (or heresy) that adherence to religious law redeems mankind before God.
A judicial or quasi-judicial proceeding, or a group of people which conducts such proceedings, which is without proper authority, and often acts abusively or decides unjustly.