'Popular justice' is initiated by the people, and the level and severity of punishment used to enforce popular behavioral norms are closely related to popular opinion. Many of the elements of popular justice in Northern Ireland in the 18th and 19th centuries have survived into the 20th century, coinciding with the coercive and repressive laws used by Britain in Ireland. A primary feature of popular justice in Northern Ireland is the dialectical relationship between certain sections of the community and the popular system of justice developed by the Republican movement. A strong sense of justice exists among the people, and if the Provisional IRA goes beyond the popular perceptions of justice in the Nationalist community, the people indicate this through various public protests. Another feature is the close relationship between the formal and informal systems. On occasions people have used both the Provisional IRA and the Royal Ulster Constabulary, and from time to time the authorities have recognized the informal system of justice. There are similarities between the popular and informal systems as well. Overall, both systems have used summary and often brutal dispensations of justice. They differ fundamentally in their sources of power, one from the Parliament and the other from a tradition of physical force supported in Nationalist areas. 41 references.